Twitter invented in 1935? - <AUTHOR> http://www.infomarketingblog.com/twitter-invented-in-1935/

<comment><USER2> Ha - not only that, but the "Notificator" (love that name) had a _revenue model_!!!

</comment><comment><USER3> OK, but how do you tell your friend which notificator to go look at? While you're telling them that, couldn't you just tell them the message too?

Twitter's main point is that you automatically get updates from people you like, not that you can post things in public.

<comment><USER4> This just in! 1935 twitter didn't work out.

<comment><USER5> Which makes me wonder if 2009 twitter will work out and become profitable.

</comment></comment></comment><comment><USER6> Twitter is just one decent take on real time pub-sub systems, which has been around for a while, previous incarnations include mailing lists, usenet groups and various forums etc. Twitter simplified the pub-sub of short messages from/to mobile devices and takes advantage of the aggregate knowledge. I think Twitter will be successful (profit!) in business marketing/networking, simply because it makes pub-sub simple.

I personally will probably never create a twitter account to follow or be followed because I'm more comfortable being a private explorer/observer (reading thousands of feeds and commenting occasionally)

</comment><comment><USER7> Is this related? <http://notificator.com/>

</comment><comment><USER8> Twitter was invented when they first used the smoke signals.

</comment><comment><USER9> No.

</comment><comment><USER10> Oh man - I was listening to public radio this morning and the guest actually said that he thought the inventor of Twitter would go down in history alongside Alexander Graham Bell and Samuel Morse.

It's mildly innovative, but let's not go nuts here..</comment>


Tony Stubblebine on how Odeo gave birth to Twitter and took over the world - <AUTHOR> http://www.stubbleblog.com/index.php/2009/06/the-real-lessons-from-twitter/

<comment><USER2> I'd love to see a discussion here about one topic from that post in particular: what are best practices for changing direction as a company.

<comment><USER2> Some of our specific problems:

We were too big, so we were paralyzed a bit by the idea that we were going to have to lay people off. Maybe I'm not giving us enough credit because we went from thinking podcasting was everything, to thinking we needed to find something else, ran five different experiments, ran at least two hackathons, and built and launched Twitter in seven months. But it _felt_ paralyzing to think about a radical change of staff.

We had middle management (me and a VP/Product) who arrived thinking our job was to make people productive. If you just wanted to experiment all day, why the hell were we hired? Somebody really needed to say: guys, we're changing modes. I think I probably needed to hear that multiple times.

We had investors who got bought out. As one said, "Ev is going to either be remembered as a genius or as an idiot." He was very gracious about it, paid more than he needed to for Odeo and then I believe let many of the investors back in when Twitter got funded. But at the end of the day CRV was the primary backer of the company that built twitter and Union Square is the primary backer of Twitter.

Once you change direction, when do you say "this is it" and actually sit down and figure out how you're going to make it happen? Because for a lot of people at the company, so many changes in direction made it hard to know for sure that Twitter really was the new direction.

</comment></comment><comment><USER3> I think it is very interesting that they did internal Hackathons to find a new direction for the company.

Wish I could just get together with a group of people and do hackathons until we hit on the right thing.

<comment><AUTHOR> I think Odeo was unique in this regard. I think it comes from having an engineering driven culture, rather than a management driven culture.

Also, it is very surprising but a lot of startups still think that ideas should come from the top, rather than anywhere in the organization. I could write a whole book on this.

<comment><USER2> I think it came from the Odeo founders, Ev and Noah. When they have an idea, they can be very forceful personalities. But when they're unsure, they both were good listeners and open to all possibilities.

</comment></comment></comment><comment><USER4> Best blog post I've read here in a while.

</comment><comment><USER5> This is much, much better than the cliche title suggests.

<comment><USER2> Wait, what? Do I need to retitle it?

<comment><AUTHOR> How's the new title? ;-)

<comment><USER2> I think it would narcissistic to say that I like it better. But I'm glad you like the post. Thanks for posting it here.

<comment><USER6> FYI -- your blog seems to be down: <http://downforeveryoneorjustme.com/www.stubbleblog.com>

Would like to read the post but can't, currently :)

<comment><USER2> Looking into it. It's back up now, but if it goes back down here's the google cache: [http://22.214.171.124/search?hl=en&q=cache%3Ahttp%3A%2F%2...](http://22.214.171.124/search?hl=en&q=cache%3Ahttp%3A%2F%2Fwww.stubbleblog.com%2Findex.php%2F2009%2F06%2Fthe- real-lessons-from-twitter%2F&aq=f&oq=&aqi=)</comment></comment></comment></comment></comment></comment>


Request HN: I need a mentor/advise - <AUTHOR>

Hey, I've been browsing HN for a few years now. When I first found this site I remember feeling super excited. Reading all of the success stories on here made me feel optimistic that maybe I could do the same.
But now I don't feel like that any more. I've ran out of plan B ideas and it's becoming increasing clear where my failures lie. Experience.
To explain, earlier I was thinking to myself, "I could whip up a online store for those [products] and sell them for way more". But then I thought, but where do I keep the stock? I could rent a warehouse but how do I get the money? Won't I need forklifts for a warehouse, etc? Then what about delivering the products? I can't just go to the post office, the products are too big.
This happens a lot with my bigger/more expensive ideas, I have no 'business' friends or family to talk to about how to startup certain ideas and I don't have the money to pay someone to do it for me. So I've been trapped with building less imaginative ideas because they're easier and I know how to do that.
So I'm looking for somewhere or someone I can get advise from. I have my brain and a little money to offer. Thanks. <comment><USER2> Entrepreneurship is all about learning, because you don't really know what it is until you do it. Start a business, realize it doesn't scale (like consulting). Start another business, have it scale better (get paying clients, but realize you can't scale with marketing). Start another business, one where investing in marketing works. ...etc...

I think it's a long process, one you have to learn by yourself. It's not about having ideas, it's about learning how everything works together.

Just like you, I'm broke and alone, and it's only making it more difficult. Last advice: read, a lot. Amazon is your friend (start with Seth Godin maybe).

</comment><comment><USER3> The best advice I can give you is to go out and meet business type people. If you live in a community that has business/startup meetups I would attend some of those and just meet/talk with the people. Ideas will start to flow and you will have people to bounce ideas off of. Also read as much as you can about business and everything related to it. Don't be discouraged, the right idea/opportunity will come.

<comment><USER3> Also if you need any specific advice, I would be happy to help any way I can. My email can be found in my user information.

</comment></comment><comment><USER4> "This happens a lot with my bigger/more expensive ideas"

"So I've been trapped with building less imaginative ideas because they're easier and I know how to do that."

I would argue that this is a very fatal flaw in your thinking that you should correct asap. You're making it impossible for yourself to succeed.

It's exceptionally difficult to start big / expensive / complex businesses without the ability to raise equally large amounts of capital. And raising large amounts of capital for that type of business is nearly impossible without the experience and or connections you'd properly expect it to require.

So let me put this out there: do not try to start such types of businesses, unless e.g. you've got the kind of wind at your back that Elon Musk did after selling PayPal (to then start something like Tesla or SpaceX, which required immense capital and amazing execution, drawn on from huge amounts of experience and plenty of brilliant influences and employees).

Imgur, Reddit, Craigslist, Facebook, Twitter, Google, YouTube, eBay, Microsoft, LinkedIn, and on and on. These were not massive, highly complex concept businesses to get started (some of them become very complex of course). In fact, they were small'ish concepts, narrowly focused, with the capacity to snowball massively.

Zuckerberg didn't need a billion dollars to build the first version of Facebook, and it wasn't complex. Ditto Twitter or YouTube or Snapchat and so on. Facebook started at one college, Zuck knocked over one bowling pin market, and then the next and then the next.

What's big and elaborate about the core of Candy Crush? Draw Something? Absolutely nothing. You'll find most successful businesses start out very simple; in hindsight, they make you think: holy shit, that's so stupidly simple why didn't I think of it.

Even difficult to start businesses typically start from a simple premise or a simple attack approach. Take Tesla for example, Elon didn't jump right into trying to make the model S (or a mass consumer electric car). He built up experience, an amazing team, capital, manufacturing experience, technology, a sales channel, a brand, global hype - by first building the low-production roadster for a small group of rich people (which could afford it, which then helped fund the next level of development).

Simple idea + easy to get started + low cost to build first version/s + the ability to snowball massively = what you should be building (strictly my opinion). It helps if you can derive sales from day one to use customers as your funding, instead of giving up equity, but that's not a requirement depending on what direction you want to go.

Also, very importantly: the idea itself matters a lot less than you may think. Ideas are nearly worthless, a dime a dozen. For every Facebook, there are dozens of people that had the same idea and didn't execute / didn't ever build it.

This is one of my favorite articles on this topic:

[http://cdixon.org/2010/08/21/the-bowling-pin- strategy/](http://cdixon.org/2010/08/21/the-bowling-pin-strategy/)

<comment><AUTHOR> I understand what you're saying. I'm aware of pretty much everything you said and I try to build startups in that way. I only work on projects that I can start small and grow. For example I had an idea for a more 'human' analytics app, which instead of showing graphs and statics would explain what was happening and ways to improve things with text. So I thought I'd keep it lean and started with just Twitter analytics and no body cared for it. I still love the idea but I don't have the time or resources to build it into the app I want it to be.

Thanks though, I do appreciate the advise.</comment></comment>


$50k competition to spot icebergs off the coast of Newfoundland - <AUTHOR> http://www.cbc.ca/beta/news/canada/newfoundland-labrador/ship-iceberg-competition-kaggle-1.4405021 <comment><USER2> All ships over a certain gross tonnage or in commercial service must use AIS to announce themselves. Seems straightforward to subtract the satellite image objects that correlate to ships announcing themselves, leaving only icebergs (making it cheap to submit follow up satellite image tasking requests at high resolution to confirm).

Cool crowdsourced challenge!

Edit: Removed US Coast Guard reference, see peeters link below.

[https://www.marinetraffic.com/](https://www.marinetraffic.com/)

<comment><USER3> Not sure why US requirements are relevant to Newfoundland. Here are the Canadian requirements:

[http://laws-lois.justice.gc.ca/eng/regulations/SOR-2005-134/...](http://laws- lois.justice.gc.ca/eng/regulations/SOR-2005-134/page-5.html#h-41)

Automatic Identification Systems (AISs) 65

(2) Every ship, _other than a fishing vessel_ , of 300 tons or more that is engaged on an international voyage shall be fitted with an AIS.

(3) Every ship, _other than a fishing vessel_ , of 500 tons or more that is not engaged on an international voyage shall be fitted with an AIS, but if it was constructed before July 1, 2002 it need not be so fitted until July 1, 2008.

I've emphasized the part about fishing vessels because that is particularly relevant here. The waters around Newfoundland are huge fishing grounds.

<comment><USER2> Indeed, I should've grabbed the Canadian requirements. Mea culpa, I sail out of the US.

AIS has been slowly rolling out for almost 13 years now, and is pervasive enough that you can be fairly confident most, of not all, large ships are announcing themselves with it. I know several blue water cruisers even with sailboats in the 30-50ft range that have it installed to prevent "death by cargo ship" in the middle of the night.

</comment></comment></comment><comment><USER4> While the Kaggle competitions are cool for students, 50K would be a measly amount paid to an R&D company or contractor to do such a job. I don't like the bounty approach to data science the same way I don't like it for software engineering.

<comment><USER5> as far as i know, most kagglers are not students, but honestly i havent seen any data on that.

I'll speak for myself, I do it because I love trying to solve interesting problems and I love data science.

thus far every competition I joined I learned something new and expanded my ds code base. I also really love the fact people post kernels and discussions I can learn from as well.

<comment><USER6> It's very difficult to win a Kaggle comp these days, not because of technical difficulties, but because you're up against teams of people with the resources to try a lot more hyperparameters than you. To a certain extent you can win with money - if you can afford to spend money on a bunch of AWS instances, that gives you more iteration time than one person with a 1080 in their bedroom. (So no, they're mostly not students.)

On the other hand the problem sets are 'real' and it's excellent machine learning experience - importanly because you have the competition element, you get an idea about how good your solution actually is.

<comment><USER5> in the zillow one, I was 41/3800, but I got over-obsessed with lb results and the first round of home sales my rank droped to 118.

however, this was my first real kaggle competition, and I only spent a few weeks on it, (I'd say about 3 total). it was also one of the more competitive competitions, with a million dollars on the line.

Its exponentially difficult to move up the ranks, but I do think its realistic to win one (though hard - as it should be). a lot of time, effort, and skills required but not impossibly difficult.

I think kaggle would do everyone a favor if they gave out awards to more people, instead of the winner take all mentality. at the very least, everyone in the top 10 should win money, not just the top 3, with 1 getting the lions share.</comment></comment></comment></comment>


AWS Amplify now supports Angular 6 apps and Angular AOT compilation - quick-basic https://aws.github.io/aws-amplify/media/angular_guide <comment><AUTHOR> Yeah, so a trip to wikipedia can answer pretty much all the comments here.

AngularJS 1.7.1 was released June 8 2018 (3 days ago), and active development is set to end June 30, with 1.7.x supported as LTS through until June 30 2021. [1]

Angular 2 - 6 is on a much shorter release cycle, with Angular 7 scheduled to release in Sept or Oct 2018. There have been steady improvements, but nothing as radical as AngularJS 1.x -> Angular 2. [2]

For familiarity's sake, I imagine working with 1.x isn't a bad choice, but personally I wouldn't recommend starting a new project with it, especially if said project expects to have a large, nested tree of components. Such a project may exceed the recommended 2000 digest cycle watchers per page, whereas Angular 2+ and the use of immutable objects and observables inherently better performance characteristics.

[1] [https://en.wikipedia.org/wiki/AngularJS](https://en.wikipedia.org/wiki/AngularJS) [2] [https://en.wikipedia.org/wiki/Angular_(application_platform)...](https://en.wikipedia.org/wiki/Angular_\(application_platform\)#History)

<comment><USER2> I work in 1.x in my day to day and agree with you - I wouldn't recommend starting new projects with 1.x as it's starting to feel its age now. Performance is a major concern unless you are savvy with how you write your code.

I really like what Vue is doing as sort of an intermediate between Angular 1.x and the new world of frontend

</comment></comment><comment><USER3> Appearently so. Imho, 1.x is still the best.

<comment><USER4> 1000% this. For a consulting shop, Angular 1.x specialty was, is, and will be hot for many years to come. From a developer stand point, there is really no need to look elsewhere other than hype.

<comment><USER5> This isn't good advise. Angular 1.X is discontinued and uses confusing patterns not used in Angular 2 , React, Preact, Vue etc. specializing in it is a very bad career move.

<comment><USER4> It is a great specialty. Sure doesn't hurt to pick up others along the way, but having deep Angular 1.x specialty 5 years from now will have you flooded with maintenance, upgrade and conversion gigs, and big ones.

</comment></comment></comment></comment><comment><USER6> Wait, we're on 6 now??

<comment><USER7> I have the same question, haha

</comment></comment><comment><USER8> Did they skip versions 3-5?

<comment><USER9> Only 3 was skipped.

<comment><USER8> Any explanation on why?

</comment></comment></comment><comment><USER10> didn't know aws had a github.io page for their oss work!</comment>


Britain posthumously pardons thousands of gay men in 'Turing law' - happy-go-lucky http://edition.cnn.com/2017/01/31/europe/britain-gay-pardon-turing-law/ <comment><AUTHOR> When this was first being discussed and debated in British Parliament I thought it was an excellent idea to help heal wounds created in the past. During that process I saw comments from some gay men saying they didn't want a pardon; they didn't do anything wrong. I'm not sure I've ever been so changed on any issue with a single statement before.

Pardon implies forgivness for wrongdoing, but these men don't need or want that, they didn't do anything wrong. The establishment that passed laws limiting love are the ones in need of forgiveness. There needs to be a legal mechanism to automatically expunge criminal records for social issues once society has managed to catch up with the people it deemed rule breakers in the past other than a pardon. A pardon is just the wrong mechanism to deliver an apology.

<comment><USER2> Another possible aspect of this, which complicates in some ways what you said in your comment, is that the earlier special pardon for Turing was, to my mind at least, a patronizing idea that cast him as an unworldly "innocent". Gordon Brown, the British PM at the time, made a statement in which he repeatedly referred to Turing as "Alan". It was obviously insincere and came across as inappropriate and condescending.

There's work to be done here, all right.</comment></comment>


Please Stop Blocking Everything but Googlebot in Robots.txt - <AUTHOR> http://danluu.com/googlebot-monopoly/

<comment><USER2> Due to this trend, the de facto crawler behaviour will be to do as Apple do and observe Googlebot's rules as if they were your own [1].

(That is assuming a given crawler follows robots.txt at all!)

[1] [https://support.apple.com/en-us/HT204683](https://support.apple.com/en- us/HT204683) (HN discussion was at [https://news.ycombinator.com/item?id=9497264](https://news.ycombinator.com/item?id=9497264) )

<comment><USER3> Reminds me of user agents.

</comment></comment><comment><USER4> Apropos archive.org: I recently found out they interpret a missing robots.txt as access denied. I wonder if that's a mistake or on purpose.

<comment><USER5> Generally, media without a license is considered "All rights reserved" by default. Archive.org may be choosing to interpret no robots.txt similarly out of courtesy (better not archive something sensitive by accident) or to minimise legal liability.</comment></comment>


Design of LuaJIT 2.0 (2009) - <AUTHOR> http://lua-users.org/lists/lua-l/2009-11/msg00089.html <comment><USER2> > I cannot guarantee it to be free of third-party IP however. In fact nobody > can. Writing software has become a minefield and any moderately complex > piece of software is probably (unknowingly to the author) encumbered by > hundreds of dubious patents. This especially applies to compilers. The > curent IP system is broken and software patents must be abolished. Ceterum > censeo.

Somewhat related, Apple seems to be filing dubious patents on Swift. Discussion from a couple of days ago: [https://news.ycombinator.com/item?id=18997302](https://news.ycombinator.com/item?id=18997302)

</comment><comment><USER3> I use luajit in a few places in my own stack (Redis, Kyoto Tycoon) and appreciate how magically fast it is. I have no idea how to approach a post like this. SSA, FOLD, it's all Greek to me. I feel pretty satisfied swapping an n^2 loop for an nlogn implementation, but this is a completely different level. Grateful for this library and for the fact that I don't have to understand it to use it (it's good to be humbled).

Also anecdotally, I think raptorjit is a kind of next incarnation of luajit. [https://github.com/raptorjit/raptorjit](https://github.com/raptorjit/raptorjit)

Actually, found this on the raptorjit readme, a list of helpful optimization resources: [https://github.com/raptorjit/raptorjit/blob/master/README.md...](https://github.com/raptorjit/raptorjit/blob/master/README.md#optimization- resources)

<comment> le-mark Note raptorjit is a fork of luajit.</comment></comment>


Single women a growing force in the real estate market - <AUTHOR> http://www.chicagotribune.com/classified/realestate/ct-re-0911-kenneth-harney-column-20160908-column.html <comment><USER2> I can't see the page because of an add that can't be closed</comment>


How Do Bikes Stay Up? [video] - <AUTHOR> https://www.youtube.com/watch?v=oZAc5t2lkvo <comment><AUTHOR> Follow up: excellent Ted talk "Why bicycles do not fall: Arend Schwab at TEDxDelft": [https://www.youtube.com/watch?v=2Y4mbT3ozcA](https://www.youtube.com/watch?v=2Y4mbT3ozcA)</comment>


Ask HN: justifying hosting costs for hobby sites - <AUTHOR>

I've got a webapp idea in mind, but I don't see any revenue potential. But as an unemployed dev I do see resume potential. The thing is I can't seem to justify the hosting costs. My best guess is it would be about $100/mo. But, I see on HN a lot of people whipping up simple webapps and sometimes complex webapps with out any revenue being generated, and just running it for the fun of it. So how do people justify expenses similar to that that don't justify the ends? A line must be drawn, no matter how much fun it is. Especially since as I said, I am unemployed. <comment><USER2> To get at least a resume-building prototype going I don't see why you would need to pay $100/mo in hosting.

Now, if you begin to grow such traffic that you need to shell out $100/mo in hosting, then maybe you have something interesting going that you can probably find a way to make some revenue from it (or at least $100/mo)

There is always the option of using S3 or App Engine, but it really depends on your app. So, if your goal is Resume Building, at least start with cheaper hosting and build a prototype.

I use a VPS that costs me $49/mo and I use that for hosting any prototypes or early projects.

</comment><comment><USER3> I pay about $20/month at SliceHost and never needed more than the cheapest slice.

</comment><comment><USER4> "But, I see on HN a lot of people whipping up simple webapps and sometimes complex webapps with out any revenue being generated, and just running it for the fun of it"

I really don't think most of the hobby projects are paying anywhere near $100/mo for hosting. Is there something specific about your project that would need a $100/mo webhost?

</comment><comment><USER5> you need more SysAdmin friends.

seriously, almost every real SysAdmin has a server in a datacenter somewhere, roaring away and burning through power, often doing little more than personal email, spamfiltering, and personal website/filesharing. Usually they love giving friends free hosting for little personal projects, as that justifies the existence of that co-located box that allows the SysAdmin to keep his or her skills up to date. You know how open source programmers are proud when other people use code they provide? SysAdmins feel similarly when we get to host/support something cool.

I mean, if you were employed, I'd say to go buy a VPS (unless your idea involves streaming movies or, ah, 'adult content,' there is no reason why your hosting bill needs to be more than $20/month. Less if you are willing to deal with a underpowered server, or one of the 'up and coming' providers.)

</comment><comment><USER6> I think you are way off the mark with hosting fees. Look at this page from inmotion hostings business plans [<http://www.inmotionhosting.com/hostingplans.html>]

Even the _costliest_ is only $19/mo.

</comment><comment><AUTHOR> I estimated $100 because it is sort of a niche filehost that also has an application that would be spidering small parts of the internet to find content. I can see my low traffic site burning through 500GB/mo in bandwidth which would be about $100 at slicehost.

</comment><comment><USER7> appengine is free, and you can get a low end VPS for $6-$20/mo from prgmr, slicehost or linode, and you can use even a low end VPS for multiple low- traffic sites. It does not cost $100/mo for a hobby site.

</comment><comment><USER8> Also consider Heroku if it's a ruby webapp you're building. It's free until you need more resources, and is zero-fuss to get something deployed and set up.

</comment><comment><USER9> Of the $20/month sites, any recommendations for RoR host?

</comment><comment><USER10> Any specific reasons why you think it would be $100/mo?</comment>


Ask HN: Building a Brand with .Net or .Com? - <AUTHOR> I often hesitate buying a .net website since I am afraid people will type it as .com and go to the wrong site.
Although I see many startups using .net, .co and even .io
What is your opinion on building a brand using a domain that is not .com? <comment><USER2> I tested ad using betterpro.net versus a specific .com name and the .com got way better CPC. Not saying that's always the case but just giving you my experience.

</comment><comment><USER3> '.io' is fine if you're a tech start up I think. Avoid .net and .co since they are sometimes associated with spam by some webmails.

</comment><comment><USER4> .io is more expensive right now because it is fashionable for tech startups</comment>


Invented by OpenBSD - glass- http://www.tedunangst.com/flak/post/invented-by-openbsd <comment><AUTHOR> I've never understood why anyone wouldn't just use OpenBSD if you're going to use a BSD. I'm sure there are reasons, there must be, but OpenBSD has a long history of having really great source code that's useful just about everywhere (hint: you're using OpenSSH almost assuredly on every linux box ever, and it's fantastic). To me, as a developer I get the whole NIH thing. I really do. I just don't get why you'd choose "here" to be somewhere that doesn't include all the amenities in the first place.

<comment><USER2> Some main differences:

\- LLVM/Clang (it's a matter of taste, but it's also the feature :-) )

\- FreeBSD Jails and Mac (These are extremely strong security features if implemented correctly. Especially jails are really undervalued/misunderstood IMHO.)

\- State-of-art network stack (faster than any other BSD or Linux. Supports technologies like NetMap)

\- ZFS support (important for both desktops/servers)

\- PF version runs on multiple cpus (OpenBSD's version is more advanced though)

\- DTrace (although not mature enough IMHO)

\- Better hardware support (e.g. wifi cards)

\- BHyve (virtualisation)

\- Capsicum (security)

Other little things like:

\- Unmapped VMIO buffers \- Variable symlinks (used under jails)

Now generally speaking, choosing an operating system due to bigotry and what- not is stupid. Most of the times, engineers go with what they need: If you need a secure bastion, OpenBSD gives you more although FreeBSD can be turned virtually impenetrable as can Linux. OpenBSD comes with more bells and whistles on this particular area though.

So all in all, it boils to what you need. The major reason why people choose FreeBSD over OpenBSD is because the 'security level' of the OS is more than acceptable while retaining a much better hardware support.

<comment><USER3> Can't argue with that, although:

> \- FreeBSD Jails and Mac (These are extremely strong security features if > implemented correctly. Especially jails are really undervalued/misunderstood > IMHO.)

Aren't these are only necessary if you let people you don't trust into your system?

> \- PF version runs on multiple cpus (OpenBSD's version is more advanced > though)

Personally I dislike running PF on FreeBSD as it requires me to resort to old docs and use old syntaxes.

> \- Capsicum (security)

Isn't this being ported as we speak?

<comment><USER4> Jails also have resource limits, so you can have a group of processes that are related, but not started from the same executable, be held to a certain amount of CPU, memory, etc usage. They're also useful in testing/debug situations; coupled with ZFS' copy on write features, they let you quickly create identical environments which can be real helpful in trouble isolation.

</comment></comment></comment></comment><comment><USER5> "[NetBSD's] reallocarray was [just] fixed to behave like OpenBSD. Now it's a 13 line replacement for a 10 line function. But at least it doesn't have any code written by an OpenBSD developer."

<comment><USER6> NihBSD.

<comment><USER7> >> Was it really worth replacing one ten line function with another ten line function just to be different?

> NihBSD

Or SourgrapesBSD ? It's not clear that this was written "just to be different".

</comment></comment></comment><comment><USER8> The post on executable memory is a hundred times more interesting than this: [http://www.tedunangst.com/flak/post/now-or-never- exec](http://www.tedunangst.com/flak/post/now-or-never-exec)

</comment><comment><USER9> The article missed:

1) W^X protections

2) ASLR

3) Stack canaries

4) strlcpy

5) OpenSSH!

6) Heap guard pages

7) Software NX

8) Etc.

Maybe project PAX invented some of those, but massive deployment was in OpenBSD first. Well if you can call them massive..

<comment><USER10> I think you missed the point of the article.

<comment><USER9> Probably.

Edit: Yes, I missed it.

</comment></comment></comment><comment><USER11> The changes introduced are potentially extremely damaging. Take for example:

[https://github.com/libressl- portable/openbsd/search?utf8=%E2...](https://github.com/libressl- portable/openbsd/search?utf8=%E2%9C%93&q=reallocarray)

<comment><USER12> What's damaging about reallocarray?

<comment><USER11> Did you read the article?

NetBSD's implementation, specifically with regard to how it handles deallocation, diverges from OpenBSDs - though its documentation is wrong.

LibreSSL (for example) will compile just fine on NetBSD, but as the logic of the two implementations differ so too will correct memory management in LibreSSL. This is just one example of how a port of secure code can be made insecure.

So it doesn't have to do with reallocarray specifically. It has to do with drawing out the security implications of the article under discussion.

</comment></comment></comment><comment><USER13> NetBSD's strtoi and strtoimax seem like the better alternative to strtonum.

1\. It is defined for intmax_t instead of long long.

2\. It supports various bases. (At least I regularly need hex or base36)

3\. It can deal with trailing characters.

4\. There are matching strtou and strtoumax operations

It's of course bad if NetBSD introduces an strtonum, which behaves differently from the OpenBSD one. But maybe the OpenBSD folks should look into strtoi and strtoimax instead of blindly following their "invented here" principle...

<comment><USER14> That's basically all mentioned in his post about the design [1] from 2011 and he seems to dismiss all these cases.

Is that reasonable? No clue, I don't write/know/do C..

1: [http://www.tedunangst.com/flak/post/the-design-of- strtonum](http://www.tedunangst.com/flak/post/the-design-of-strtonum)

<comment><USER13> I don't think it's reasonable. The way they implemented strtonum might match their particular use case in OpenSSH/LibreSSL. But if they want to make it a libc function and popularise it then they should concern themselves with other use cases and opinions, especially when they pick a bold name as strtonum. It's not a surprising outcome that others are reluctant to follow them and they have clashes in behaviour or naming.

</comment></comment></comment><comment><USER15> Why do people use NetBSD over OpenBSD? Serious question.

<comment><USER16> And related, why do people choose *BSD over Linux? (I'm genuinely interested, and not trying to start a flame war). I've used both OpenBSD and Linux on my personal computers, but only Linux for servers (mainly due to ease of setup). My understanding is that Linux has marginally better performance than any of the BSDs.

<comment><USER17> I initially went back to it over the way systemd was handled on Linux. Nowadays, I've really grown to appreciate the minimalism and the slower, more thorough pace of advancements. I find that being _too_ cutting edge just tends to lead to more problems in production. I also really like the development model, and most design differences I read about (one quick example: /dev/random behavior) more in the BSDs. Lastly, lots of features I like a lot more. ZFS over btrfs, pf over iptables, etc.

<comment><USER18> I always heard good things about the BSD's and I was forced to use pf in my previous company..

but it was systemd that pushed me towards it, I'm not bound by random binaries that do random things with little documentation- everything is very clearly understandable and I can even guess what things will be doing with a large degree of accuracy.

the whole thing seems much more "sane", but- Linux is a better desktop in my opinion.

</comment></comment></comment></comment><comment><USER19> I don't understand how one can claim to "invent" reallocarray. Glib has had g_realloc_n() since 2010, but its not something being touted as a huge invention. Its a tiny helper. Very useful, but quite obvious.

<comment><USER18> I think the Author is saying that people often use BSD code or ideas and reimplement them to be fundamentally incompatible yet using the same name.

this means that, as a developer, when calling these functions you can't be sure of if you're calling it in a safe way.. openBSD makes code deliberately designed to be portable, and other BSD's make it non-portable by altering it in odd ways, yielding dangerous consequences by reusing the namespace.

</comment></comment><comment><USER20> except the 0 behavior has been restored

<comment><AUTHOR> Today. Timestamped almost right with this article. I'm sure it is correlated and not causal, but I'm also pretty sure the root cause for both is the same.

<comment><USER21> I'm not sure what your supposition about the root cause might mean.

NetBSD very recently imported these functions (reallocarray and strtonum) to libc after much objection (over several years actually) to their poor APIs, yet finding that they crop up time and again in code used in base (and then multiple copies exist, in out of the way places). So, as a pragmatic solution they are now available from libc if _OPENBSD_SOURCE is defined. Cleaner API functions were proposed, with wrappers which would provide equivalent functionality for the OpenBSD functions. Some difference was noted, and recently fixed in these wrappers.

The root cause for the NetBSD changes then, seems to be that these functions keep cropping up, and the job of libc is to provide commonly used functions.

I believe the intention is, that the cleaner API is proposed to replace the original OpenBSD ones, which are not properly portable (strtonum for instance, returns hard coded english error strings in ASCII)

The root cause for the blog entry by Ted Unangst is probably that he is an OpenBSD developer and was involved in creating these functions, which are now being criticised.

These root causes don't seem the same to me.

<comment><USER14> You seem to have a much better understanding of the situation than I do. The remark about the hard coded error strings was interesting though, so I looked at the implementation [1].

I .. am not sure why that would be considered not portable? Admitted, I'm neither into C nor do I have experience in the field, but .. that seems to be easy to read, contains clear/concise error messages _on top_ of clear error codes.

1) Any consumer can ignore the string and map the error code to a message in Klingon or whatever else, no?

2) The function name is in ASCII/English. So are the parameter names. Most of your C code is probably reading ~somewhat~ like english, and usually is restricted to ASCII? Is it really a problem that this method returns both a well-defined number and a simple string in case of an error?

Back to the first line: I .. am certainly clueless here and just watching from the sidelines. But I'm kinda serious about the questions and genuinely curious why you object to that part of the implementation?

1: [http://cvsweb.openbsd.org/cgi- bin/cvsweb/src/lib/libc/stdlib...](http://cvsweb.openbsd.org/cgi- bin/cvsweb/src/lib/libc/stdlib/strtonum.c?rev=1.7&content-type=text/x-cvsweb- markup)

<comment><USER21> for 1, the consumer is properly the user not the programmer.. and the user cannot ignore the error string in favour of the number if the programmer provided only that. Since the documentation specifies the error strings,

for 2, the function can be called (as can any C function) from a source character set other than ASCII, as the compiler should handle that. The name is technically english its true and programmer needs to know some english, perhaps.. but the user does not need to know that

if the error code is used, then the error string is superfluous, and C library functions are not in the habit of providing superfluous information. C is pretty low level after all.

Here is more reading about the objections the NetBSD folk had with strtonum(3)

      http://mailing.netbsd.tech.userlevel.narkive.com/mZ37nlai/strtonum-3-from-openbsd

<comment><USER14> Still confused.

What is a user in your reply? I mean, an end user / my mom isn't going to call strtonum? Some developer does. And said developer can absolutely ignore the string's content?

Test for success: errno is 0, errstrp is NULL Handle error: Use errno or errstrp - the latter gives you a bit more information (reports a different error for invalid ranges, too small vs. too large).

But if you don't care, errno is fine, no? And we're still talking about the programmer here, as far as I'm concerned.

Ted has a description of his intentions here [1]. I guess I'm confused why there's a fuzz about it, because technically this method should be good enough? I do have to shake my head at the "Even if intmax_t probably would have been a better choice, I think we're sticking with long long just because it frustrates people unwilling to admit it doesn't make a difference." remark, but .. other than that? Does it .. matter?

1: [http://www.tedunangst.com/flak/post/the-design-of- strtonum](http://www.tedunangst.com/flak/post/the-design-of-strtonum)

<comment><USER21> Yes, the user is the person who runs the program that they didn't write. They don't know that they called strtonum()

testing for errno == 0 is not actually useful, since errno is not set except on error (that is by design of errno, it is always an indication of what the last error was, not that there was an error)

and errstrp doesn't give the Klingon user you mentioned any information at all, since they can't read English.

fafner said it better than I in [https://news.ycombinator.com/item?id=9184734](https://news.ycombinator.com/item?id=9184734)

and yes it does matter, for a standard libc function, because if you don't take care about setting standards, then your standards will be a mess.</comment></comment></comment></comment></comment></comment></comment>


The Dipole Drive: A New Concept for Space Propulsion - <AUTHOR> https://www.centauri-dreams.org/2018/06/29/the-dipole-drive-a-new-concept-for-space-propulsion/ <comment><USER2> I almost believe in this ... but no.

It's just a parallel plate capacitor, with holes in the plates that allow the surrounding plasma to pass trough. The question is:

 _Why a plate capacitor with holes in the plates inside a diluted plasma is not a perpetual mobile?_

Let's assume that initially the device is with speed 0 inside a huge bath of plasma that is also at speed 0. We charge the two plates of the capacitor instantly and magically. In this model and the calculations the ions never hit the plates because they have holes, so the plates never discharge. There is some energy in the electric field of the capacitor.

Now the device is operational and it starts to move, the ions also move. Now the devices and ions have some kinetic energy.

* If we believe the whole idea the ions just go away, and the plates never discharge, and new plasma enters the device, so it continues to accelerate forever. So the total energy of the system increase and increase, that is something impossible.

* If we don't believe the whole idea, the problem is that the ions accumulate outside the plates in some kind of ion cloud, even if they never hit the plates. Initially the effect is small, but eventually the charge of the ion clouds compensate the charge of the plates and the plasma inside the device feels no net force, so the device moves at a constant speed. Essentially, some part of the energy that was stored in the electric field was transformed into kinetic energy, but there is only a finite amount of it, so the device must reach a maximal velocity.

\---

There is some complications, because in the Solar system the plasma is not static, because there is solar wind. So, just imagine that you pick a reference frame (i.e. starship) that is moving at the same speed of the solar wind. In this reference frame (i.e. starship) initially the plasma looks static and the giant capacitor is moving. When it is turn on, there is some energy in the electric field and some kinetic energy. After a while, the charges are redistributed, and the speed of the giant capacitor changes, but only a finite amount, it can't continue accelerating forever. If you see the scene from the normal reference frame (i.e. the Sun) the device is initially static and after a while it is moving with a cloud of ions around it, but the total change in speed is the same.

I guess there is some drag, and the final speed in the starship reference frame is 0 and the final speed in the Sun reference frame is the same of the speed of the solar wind.

\---

About other comments:

* I agree that the momentum transferred to the protons and electrons is different. With some assumptions the ratio is 43, but in a moving device in a moving solar wind the calculation is more complicated. The exit speed of the electrons is 100 times faster than the solar wind, so it makes almost no difference. The exit speed of the proton is roughly the speed of the solar wind, so the calculation must be fixed, but there is a net effect that is no 0. (Until the ions cloud accumulate enough charge.)

* In an ion thruster the first step is to ionize the gas. Here they start with an ionized gas. The difference is that in a ion thruster they separate the positive and negative field.ions, so they waste some energy in the separation and then they accelerate only the positive ions. The separation of the ions is an active process, not just a static electric

* Hat tip for sandworm101 for the comment [https://news.ycombinator.com/user?id=sandworm101](https://news.ycombinator.com/user?id=sandworm101)

\---

About the article:

> _The acceleration of the electrons is a form of drag, which is provided for > by loss of spacecraft kinetic energy. It therefore could, in principle be > used to generate electric power, partially compensating for the power > consumed to accelerate the protons._

This makes no sense. The acceleration of the electrons create some thrust in the wrong direction, but it's not like a drag, it's like a thruster in the wrong direction.

> _To see what the performance of a dipole drive might be, let us work an > example, assuming a 500 W power source to drive the system. The electron > current negates about 2% of the thrust (1 /43rd) produced by the proton > current. The maximum possible jet power is thus about 490 Wj. Assuming > additional inefficiencies, we will round this down to 400 Wj, for a total > system electrical to jet power efficiency of 0.8. The relationship of jet > power (P) to mass flow (m) and exhaust velocity (c) is given by: P = mc^2/2_

I'm not sure that mixing thrust and energy is a good idea, but anyway they assume that the efficiency is 80% and use the usual formula to get the speed. The problem is that assuming that only a 20% of the energy will be wasted is optimism, not a real calculation. How much energy is lost due to the collision of the ions and the plates? How much to recharge the plates? How much is lost in real drag? How much is lost as heat? ... There are a lots and lots of factors, and then you have to consider the nasty ions clouds.

<comment><USER3> Why are you even talking about it as a perpetual motion machine? I don't see any claim anywhere in the original article that it is. He even talks about nuclear reactors used to power it.

You're refuting a claim that doesn't even exist.

And in doing so, you're also assuming the particles around it have "speed 0" when the explanation clearly describes individual particles as having non-zero velocity so that they can enter the space between the two plates on their own, as it is claimed that there would be no net electric field outside of them.

<comment><USER2> They never claim it is a perpetual motion machine. They just invented a machine and if it works as intended it would be a perpetual motion machine, so we know it will not work as intended. [1] They don't claim that it is a perpetual motion machine, if you analyze the consequences of their claims you conclude that it is a perpetual motion machine. I guess they didn't notice this, it's not an obvious consequence in the usual reference frame.

In my description I change the reference frame because it's much easier to do the calculations. In the reference frame that moves at the same speed of the solar wind the plasma has speed 0, but it doesn't mean that all the particles have speed 0. It means that the number of particles that are moving in one direction is (almost) equal to the number of particles in the opposite direction. [2] It's like the air inside a quiet totally sealed room that is left alone for a few days. The air "doesn't move" but the oxygen and nitrogen molecules are moving very fast. The speed that they have is related to the temperature. But in bulk they don't move and if you put some small pieces of paper or strings they will not move (unless they are really tiny). If you have some container like a glass inside the room the molecules that are inside the container will change constantly, but the number of molecules inside the container will (almost) no change. The problem in my version of the experiment is not that the device will get empty.

[1] Assuming we don't need to change the current accepted laws of physics to explain this. It would be even more groundbreaking.

[2] There are more accurate technical description but this is good enough.

<comment><USER3> Am I missing something, or isn't this (at least while between the plates) just the same phenomenon as the electric fields that are used to deflect electron beams in some CRTs?

[https://en.wikipedia.org/wiki/Electrostatic_deflection](https://en.wikipedia.org/wiki/Electrostatic_deflection)

Obviously CRTs don't contain perpetual motion machines. So there must be some way in which energy is lost in the plates.

(Note that when I say it's the same phenomenon, I'm talking about a force acting on charged particles. The initial direction of the particles is different, though. In this dipole drive, the charged particles are initially moving roughly perpendicular to the plates, while in a CRT the particles are moving parallel to the plates. But that shouldn't be relevant to the energy needed to accelerate them.)

<comment><USER2> In a CRT, when the electrons hit the screen they go and complete the circuit, so the negative charge doesn't accumulate.

Also, when the electrons are extracted from the cathode it gets a small positive charge, but this charge also circulate and is not accumulate. Moreover, it's the charge that eventually neutralize the charge of the electrons.

I think there are no special wires to make this happen, the current I very small and the charge is redistributed by the supporting parts.

A good comparison would be to use a CRT where the screen is split in two perfectly isolated parts. After a while the half you are sending the electrons two become too charged and it deflects the electrons.

<comment><USER3> > _when the electrons hit the screen_

I am NOT talking about the main electron gun. I am talking about the deflection plates.

Just to be perfectly clear, a CRT has three active components:

1\. Electron gun to create a beam of electrons aimed in the direction of the screen.

2\. Vertical deflection to move the beam up and down.

3\. Horizontal deflection to move the beam side to side.

Here, you are talking about #1, and I'm talking about #2/#3.

<comment><USER2> If you have an ideal CRT and don't want to adjust where the electron bean lands, you don't lost any energy in #2 and #3. You can replace #2 and #3 with some perfectly isolated plates with a fixed amount of charge that have the same charge forever.

If initially the position of the beam is in the center of the path , a charged #2 and #3 will change the direction and in a smaller amount the velocity of the electrons. The energy to change the velocity comes from the energy in the electric field, not from the plates.

You can say that this energy is energy of the electric field or that it is potential energy of the electrons in the electron beam. Both descriptions are accurate and give the same result. Just remember to not count it twice.

Now the question is where does the energy from the field or the potential energy of the electrons came from. The answer is that the repulsion has a small but not 0 effect outside the main part of the capacitor and this creates an electric field outside. To align the beam at the center you must overcome this small force, so you must add some energy to the electron (in this case it's easy to think in the potential energy of the electron). Perhaps the comment from ballenarosada is more clear [https://news.ycombinator.com/item?id=17432975](https://news.ycombinator.com/item?id=17432975)

In a normal CRT the electron bean is created from a high voltage source so it moves fast, and the electrons initially move inside wires, so you usually ignore the small potential field of the capacitor far away. If the charges move slowly and freely then you must consider the effect of the electric field outside the capacitor.

</comment></comment></comment></comment></comment></comment></comment><comment><USER4> This won't work. The basic idea about the protons gaining more momentum than the electrons is valid. But the dipole creates an opposite field outside of the charged plates. Protons will be decelerated until they pass the first, positively charged plate, then accelerated through the plates, then decelerated back towards the negative plate.

This is all clear if you consider the ions falling through a potential field. The potential is 0 at infinity, positive at the first plate and negative at the second. An incoming ion starts at 0 potential, climbs a big hill to get through the first plate, then falls down below 0. Then on the way out it has to climb back to 0 potential at infinity. So the ions gain energy inside the plates but lose it all back on either side.

<comment> T-A [https://physics.stackexchange.com/questions/12309/electric-f...](https://physics.stackexchange.com/questions/12309/electric- field-outside-a-capacitor)

<comment><USER4> The electric field outside an infinite capacitor is zero. For a finite capacitor, there is a nonzero field. The importance of the infiniteness assumption can't be understated--such a capacitor cuts the universe in half, and every point of one half has the same electric potential.

On the other hand, if the capacitor is finite, then the surface integrals over the plates are not equal.

<comment> T-A > The importance of the infiniteness assumption can't be understated

No, but as you have shown it can be grossly overstated. The field outside a finite plate capacitor falls off as a power of distance >= 2 (details depend on the geometry), while the field inside it is constant. It can therefore safely be ignored for a first order estimate of the effect.

If you want to get fancy and claim that higher order corrections invalidate Zubrin's argument, you need to actually prove it. Also, don't forget to include other effects like plasma shielding.

<comment><USER4> Well, before breaking out a higher order analysis, I'd like to at least see a real first order analysis. The argument from potential at infinity is dispositive, but let's do some practice anyway:

Let A be the area of the capacitor, and dr the distance between the plates. Let c be the appropriate electrostatic constant for the coulomb force between a proton and the charge density on the plate. At a point a distance r from the capacitor, the field effect from the negative side is, ignoring curvature effects, about

cA/r^2

The repelling charge from the other plate will be about

cA/(r+dr)^2 = cA/(r^2 + 2rdr + dr^2) ~ cA(1/r)(1/(r+2dr))

So the difference between the coulomb forces, i.e. the net force, will be approximately

(cA/r)(1/r - 1/(r+2dr)) = (cA/r)((r+2dr - r)/(r^2 + 2rdr)) ~ cA(2dr/r^3)

So the net force drops off approximately as the third power of the distance, to a first order approximation. Integrating over the radius, we have that the potential goes as -1/r^2, with the approximation breaking down near r=0.

Actually inserting appropriate constants of integration would make this argument robust, but would also just reduce to the argument from potential at infinity. Either way it's clear that the effect can't just be ignored out of hand.

<comment> T-A According to your derivation, the net force grows linearly with capacitor area. Alas, the external field of a plate capacitor with infinite area is exactly 0. You can look up the correct way to do a multipole expansion in any introductory EM textbook, or google up nice a exposition like [1].

What really matters here is that with the force on the charge falling off as a power of distance, even if you integrate force * displacement from the screen out to infinity (which you shouldn't do in a plasma, because [2]), you get a finite contribution which can be made arbitrarily small relative to the work done inside the capacitor, where the force is constant, simply by increasing the size of the capacitor.

[1] [http://student.ndhu.edu.tw/~d9914102/Teaching/EM/Paper/data/...](http://student.ndhu.edu.tw/~d9914102/Teaching/EM/Paper/data/Electric%20field%20outside%20a%20parallel%20plate%20capacitor_Project%20Paper.pdf)

[2] [https://en.wikipedia.org/wiki/Electric- field_screening](https://en.wikipedia.org/wiki/Electric-field_screening)

<comment><USER4> If you read the exposition you linked, equation 14 gives an expression for the field which is linear in the area. Again, it's pretty important that the capacitor be infinite in extent, otherwise it behaves differently.

What's the dimension that you're proposing to increase of the capacitor? The total work done across the capacitor will be fixed regardless of distance across.

<comment> T-A Eq. (14) is just the expression for a dipole. Keep reading to see the full solution in the simplest case (circular plates), Eq. (19).

Since you insist: your derivation goes wrong right at the start by, as you say, "ignoring curvature effects", i.e. by considering radial distance only. By doing that, you are effectively imposing spherical symmetry; you are not doing parallel plates, you are doing concentric spherical shells. That makes the whole exercise pointless, since it's obvious from symmetry alone that such a device could never produce a net thrust: there is no preferred direction for the thrust to act along.

To answer your final question, just look at Eq. (19): make the plate radius (R) larger.

That answer should also be perfectly obvious from the limit case of infinite plates. A correct derivation for the general case must reproduce that result in that limit. Yours does the opposite; it gets worse the larger you make the capacitor. In the infinite limit, it is infinitely wrong.

<comment><USER4> You're right, my derivation is mistaken for failing to take the z component of the force. EQ. 19 is more like it although you'll note, also goes as 1/z^3.

You're also right that all that is moot from sheathing. But an ion still begins it's journey out at the bottom of a large potential well; one which is particularly steep because of the debye length, but still just as deep.

</comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER5> This seems basically the same as an ion engine without the need to BYO ions, relying on the existing ion/electron mix in plasma being sufficient and suitable. Which makes it seem fairly credible. Potential for much higher efficiency than ion engines too if a plentiful supply meant you could sacrifice thrust/ion.

Cathode Ray tube comparison below isn't entirely valid, as the goal of a CRT isn't to generate net thrust.

<comment><USER6> I would say that a good comparison (of course the math is different, since one is monopole-monopole and another is monopole-dipole) would be saying it's like a continuous gravitational slingshot except with solar wind ions and electricity. With a gravitational slingshot, you use gravity to steal kinetic energy from the larger body (usually the planet doesn't notice); with this you use an electric field to steal kinetic energy from the passing wind.

</comment></comment><comment><USER7> > Ions entering are then propelled from the positive to the negative screen > and then out beyond, while electrons are reflected. There are thus two > exhausts, but because the protons are much more massive than the electrons, > the thrust of the ion current is more than 42 times greater than the > opposing electron thrust, providing net thrust.

Does this follow? I thought the force of an E-field on a particle is proportional to charge and field strength-- so the electrons are lighter, but will be accelerated with the same force to a much higher velocity. So wouldn't the reactive force be the same for both?

<comment><USER8> The particles are passing through a fixed distance (between the screens), wherein they experience a fixed force due to the electric field.

An electron will shoot through that distance in no time flat and accrue very little momentum. A proton will plod through and transfer far more.

For a 250V potential difference with 20m between screens, you can check it yourself here:

[https://www.wolframalpha.com/input/?i=(1+electron+charge+%2F...](https://www.wolframalpha.com/input/?i=\(1+electron+charge+%2F+mass+of+proton+*+250+V+%2F+20+m+\)+*+sqrt\(2+*+20+m+%2F+\(1+electron+charge+%2F+mass+of+proton+*+250+V+%2F+20+m+\)\)+*+mass+of+proton)

[https://www.wolframalpha.com/input/?i=(1+electron+charge+%2F...](https://www.wolframalpha.com/input/?i=\(1+electron+charge+%2F+mass+of+electron+*+250+V+%2F+20+m+\)+*+sqrt\(2+*+20+m+%2F+\(1+electron+charge+%2F+mass+of+electron+*+250+V+%2F+20+m+\)\)+*+mass+of+electron)

The ratio of those two values is 42.8.

This also makes it easy to see why heavier ions full of neutrons are _awesome_. They give a ratio of 5343.

<comment><USER9> Thank you. I was going to post the same concerns about the result being electrons accelerated much more quickly out the front, thus no net propulsion. I am glad I read the comments first.

</comment></comment></comment><comment><USER10> Huh. I don't see any obvious pitfalls here, the physics and principle of operation are quite simple.

I am struggling to come up with an explanation as to why I haven't heard about this before other than sneaky DOD stuff.

Who would like to bet me a large sum of money that there are currently operation military sats employing this......

EDIT: as epicureanideal pointed out, commenters in the article raised valid points discrediting most of the author's analysis. +/\- charged ions get same net kick in the field, comparing proton mass to electron mass is a red herring.

Overall concept still passes sniff test, just needs further analysis. It's going to be all about the angle - you need one ion species to spend more time in the field than the other to get a net thrust

A magnetic scoop with a normal ion thruster might be more practical.

EDIT 2: After further consideration, my concern here is what happens outside the plates. This works for infinite parallel-plate capacitors - you just need to have the field strong enough so one ion species undergoes more net acceleration. In practice the field outside the plates will not be zero and that could spoil everything

EDIT 3: I know nothing. E&M is hard. There will be a current around the outside as you're pumping positive ions to one side and negative to the other. This will induce a magnetic field affecting the ions being pumped through the field. I have no clue what the net effect will be.

<comment><USER11> Some of the commenters on the linked website claim it violates physics principles. Like many people here I took several university physics courses and it seemed plausible to me, but I don't have confidence in what seems plausible to me actually working. There are a lot of "oops, I didn't think about that" types of things when making calculations in physics, from my memory...

Note: After reading post by nickparker here, note that most of the commenters on the linked website who were claiming mistakes with the math seem to be wrong. Nickparker here posted links to what seem to be valid calculations showing the math works out.

<comment><USER12> It's very good example of why we need real space testing of propulsion concepts. Once we have a bunch of engineers actually living in interplanetary space, where they can do easy experimentation, we will see some rapid developments.

<comment><USER13> Not really, actually we understand pretty well electromagnetism, electrodynamics, plasma physics and numerical methods for those. We can simulate these things, so there's no need to reinvent the wheel going full Faraday at the 21st century. A few trained physicists on Earth would do, yet people get so excited wilfully ignoring all this.

</comment></comment></comment></comment><comment><USER14> I guess there's only one thing left to do. Experiment!

<comment><USER15> Yes.

Seems like this would be a fairly straightforward proof of concept experiment to fly outboard on the ISS. Basically a couple of charged screens with force transducers on the screen mounts. It would seem this is within the bounds of Figure 1, The Dipole Drive Accelerating Within a Magnetosphere.

Wish this paper had been published a year or two before SpaceX launched Elon's Tesla. They could have tested a new interplanetary drive.

</comment></comment><comment><USER16> Looks similar to Ionocraft[0], but only for low density plasma instead of an air.

[0] [https://en.wikipedia.org/wiki/Ionocraft](https://en.wikipedia.org/wiki/Ionocraft)

</comment><comment><USER17> Where are these charged screens coming from? Is it possible to just magically have charged screens that remain at the same charge regardless of all interactions or am I seeing a place where someone has to bring their own ions?

</comment><comment><USER18> Throwing positives one way and negatives the other? Wont they then seek each other out? Would not this thing create a little storm of ions to negate its thrust?

<comment><USER19> Still, a propeller works, even though the positive and negative pressure seek each other out.

</comment></comment><comment><USER20> Talk is cheap, show me the prototype?</comment>


In Norway, income and wealth are public record (2009) - <AUTHOR> http://www.sfgate.com/world/article/In-Norway-income-and-wealth-are-public-record-3283410.php

<comment><USER2> I'm glad this doesn't happen in the US. We don't need more ammo used in class wars by the mainstream media and bloggers/Twitter warriors.

<comment><USER3> There's brown on your nose.

<comment><USER2> yeah, well, it's covering your entire body.

<comment><USER3> Dr Nick said I'm suffering from Chronic Skin Failure, and I'm very sensitive about it thank you very much.

</comment></comment></comment></comment><comment><USER4> That's pretty horrible. It doesn't serve any good purpose except for the nefarious purposes of social engineers.</comment>


Stripe Global - <AUTHOR> https://stripe.com/global <comment><AUTHOR> @patrickc: "We're kicking off our betas—and seeing our first customers go live—in 6 new countries today! Delighted to take our first steps in Estonia, Poland, Greece, Lithuania, Latvia, and Malaysia. 🇪🇪🇵🇱🇬🇷🇱🇹🇱🇻🇲🇾"

[https://twitter.com/patrickc/status/1093197974744645632?s=21](https://twitter.com/patrickc/status/1093197974744645632?s=21)</comment>


Do large companies really generate 'real change' ? - <AUTHOR> http://www.portfolio.com/views/columns/2007/11/15/Innovation-At-Big-Companies#page1

<comment><USER2> Bell Labs did OK: <http://en.wikipedia.org/wiki/Bell_Labs></comment>


Show HN: Koody – The best savings accounts in the UK - <AUTHOR> https://www.koody.co/saving/top-savings-accounts <comment><USER2> I use NSandI and I didn't know about this. Thanks. Why are there 3 NSandI there?

<comment><USER3> They are three different types of account:

      Income Bonds,
      Direct Saver,
      Investment Account

It's not obvious from the Koody site until you click through on each link</comment></comment>


Social Networks are the New Blog - <AUTHOR> http://www.adrants.com/2007/09/social-networks-are-the-new-blog.php I like the title even more than the actual article... <comment><AUTHOR> I actually found this title more interesting than the actual article...</comment>


Ask HN: As an EU citizen how can I put my money into innovative tech? - <AUTHOR> I have some money and I want to invest in things like crispr, 3d printing and artificial meat. How can I do it without being an accredited investor in the states? Most of the companies are there.<p>If you have suggestions about specific companies outside of US please share. <comment><USER2> I'm wondering why you don't want to invest in the EU? Both London and Paris have very active tech startup scenes, and both are very active in the biotech and 3D-printing space.

I'm sure you have your reasons, but I'd be interested in knowing what they are.

<comment><AUTHOR> I think i miscommunicated my message I'd also like to invest in EU i just thought that US is a bit more advanced in this

</comment></comment><comment><USER3> EU citizens can qualify as a US accredited investor. SEC and startups won't care about your citizenship. Money is money and they're happy to accept as much of it as possible.

[0] [https://money.stackexchange.com/questions/35166/how-does- a-n...](https://money.stackexchange.com/questions/35166/how-does-a-non-us- citizen-gain-sec-accredited-investor-status)

[1] [https://money.stackexchange.com/questions/49838/is-us- citize...](https://money.stackexchange.com/questions/49838/is-us-citizenship- and-or-residence-requirement-for-accredited-investor-status)

</comment><comment><USER4> Invest in the EU, US startup scene is loaded with pump and dump scams and you will have a hard time filtering if you're not on the ground. In fact Hampton Creek has been an all around scam, with Target removing their products as of today.

</comment><comment><USER5> The accredited investor requirement is to protect you. If you are bypassing it then I'd use extra caution. Invest in companies closer to you so it's easier to complete due diligence.

</comment><comment><USER6> INAL; My understanding is that you can invest in startups without being an accredited investor if it's part of crowdfunding as per "Regulation Crowdfunding" [https://www.sec.gov/info/smallbus/secg/rccomplianceguide-051...](https://www.sec.gov/info/smallbus/secg/rccomplianceguide-051316.htm) .

Also, remember that the accreditation is not some strict formal process. You simply must be able to show you fall under one of the criteria. If your net worth is over 1M$ - you already ARE an accredited investor.

Would be nice for someone to chime in if there's some specifics regarding citizenship status. But I'd suspect there aren't.

</comment><comment><USER7> As someone living in Colombia, I will give you a perspective:

You have around a lot of untapped talent, probably badly paid, that will benefit more & give better returns than go to the obvious place.

\--- In a semi-related note, look how bad is the working conditions of animators in Japan:

[https://kotaku.com/an-insider-s-look-at-working-in-the- anime...](https://kotaku.com/an-insider-s-look-at-working-in-the-anime- business-1796312543)

This mean, among other things, that anyone with half-a-brain and money can get top-talent easily, just paying a fair rate.

Consider if some industry around you is like this...

</comment><comment><USER8> I've been investing in those areas quite a lot.

The best way is to invest in small venture funds, second best is AngelList Syndicates, and then EU- based equity Crowdfunding.

Platforms like Ustart could also work depending on check size.

The main constraint is to understand how much money. 20k is way different than 200k and 2M.

Feel free to reach out via email / twitter and I'll be happy to suggest a few venture firms that could work depending on your check size.

</comment><comment><USER9> If you want to make it especially easy on yourself, you can check your EU investment account for US tech based funds.

You won't be able to pick & choose the technology you invest in, but you'll get to ride the general wave for zero effort.</comment>


Observing Ultra-High Energy Cosmic Rays with Smartphones (2014) - <AUTHOR> http://arxiv.org/abs/1410.2895 <comment><USER2> I'm one of the leads on this project! We've been flying under the radar for a while now, since everyone working on this has a "day job" (mostly ATLAS/CMS physicists), and we have essentially no funding. But we are making progress and hope to eventually do a full-scale release and produce some science! I'll try to answer any questions in this thread.

<comment><USER3> Speaking of radar, many phones have FM radio receivers, which could conceivably look for radio signatures of cosmic rays. No idea to what extent the hardware is made available to software, but I just found another reason to procrastinate.

Also kudos on actually going through and doing something with this; I remember talking about using cell phone ccd's as detectors a few years ago with other grad students, but of course it never got past the chit-chat stage (I remember wanting a dosimeter in my pants to ring at me if I got too close to one of my radioactive sources).

<comment><USER2> People have approached us with this idea! I don't think we have much/any access at the API-level to radio signals. However are talking with another group which is looking to build an inexpensive RF array about possibly integrating the two networks. There is also another group which is creating a dedicated radio device that plugs into the headphone jack of your smartphone, but in this case you need a special piece of hardware and the phone is basically just acting as readout/internet access. It's a cool idea but we're trying to show that it's possible to do science with the existing hardware that people already own!

</comment></comment></comment><comment><USER4> Ha, we had this idea quite a long time ago (2008) when "apps" really started becoming a thing. I think this works if you were in a densely populated area and a significant fraction of the population was listening, but that was always a pipe dream.

On a related note, when a 10^19 or above event hit a densely populated area, there's a decent sized ionization column near the center of the shower that could likely lead to cancer. Theres probably 100 to 1000 or so events like that in an area the size of the Bay Area.

Edit: I took out a part talking about noise after I glanced at the paper, but I would still be worried about it because the area of the detector (aka camera sensor) is roughly equivalent to the area of the electronics (ADC, CPU, Memory, etc...) in a smart phone, whereas most surface detectors have a huge scintillation footprint compared to the electronics footprint.

<comment><USER5>
      On a related note, when a 10^19 or
      above event hits a densely populated
      area, there's a decent sized ionization
      column near the center of the shower
      that could likely lead to cancer.
      Theres probably 100 to 1000 or so
      events like that in an area the size
      of the Bay Area.

Ha! Oh man. That'd be the best alert a smart phone could ever show me.

      *beep*
        You've just been irradiated by powerful
        cosmic rays from outer space. Your risk
        factor for certain forms of cancer has
        increased by 0.013%.

I really would want to know if I was suddenly showered by cosmic rays, and my location within the crowd-sourced area-of-effect, but I wonder if an app could transmit it's sensor noise to a central server, and receive accurate results aggregated from all other app instances very quickly. I figure there'd be a lag of maybe a couple of hours or more.

Reminds me of this other site, which provides air quality stats:

[https://plumelabs.com](https://plumelabs.com)

<comment><USER6> And the alert tone could be ICQ's "Uh-oh".

</comment></comment></comment><comment><USER7> When it comes to detecting radiation with smartphone, it is possible / known. Two friends of mine made it as a scientific projects when they are still in high-school: [https://cds.cern.ch/journal/CERNBulletin/2014/40/News%20Arti...](https://cds.cern.ch/journal/CERNBulletin/2014/40/News%20Articles/1756279)

<comment><USER2> We read about them! Very cool project, especially from high-school students. A lot of people got onto this idea about the same time. See also CellRAD, which is an app that is supposed to act as a dosimiter to detect when you are near radioactive sources. It's been known for quite a while that silicon pixels can detect ionizing radiation (in fact, that's why we use pixel detectors in the inner tracker layers of state-of-the-art particle detectors such as ATLAS and CMS). The problem with the pixels in the CMOS camera of your smartphone is that they are very small (in both pitch and depth) and were optimized to respond to optical photons, rather than charged particles.

We have played around a bit with implementing these radiation-sensing features, but the main goal for the CRAYFIS project (and which sets it apart from other similar projects) is to create a distributed network of phones that all work together to act as a giant telescope for UHECR events.

</comment></comment><comment><USER8> Have they started sending around apps to beta testers? You can sign up[0] and I'm pretty sure I did, but I haven't heard anything.

[0] [http://crayfis.io/](http://crayfis.io/)

<comment><USER9> Is the app open sourced? any link?

<comment><USER2> Unfortunately not open sourced (yet). The main reason is because we're physicists, not web security experts (although I do have some background in this). I was afraid that if we open source the code and make the protocol way too obvious, the bar will be just too low for some troll to spam our data acquisition servers, making it hard for us to do science. So for now we're kind of relying on good-old "security through obscurity".

In the future we hope to harden the online system further, and eventually open source the code for both the android/iOS apps, as well as the online website which functions as a high-throughput distributed DAQ with online analytics.

<comment><USER8> Have you thought about trying to partner with someone to do a Google Summer of Code (or something similar) for this? It seems specific and targeted enough that it might have a chance of getting support.

<comment><USER2> That's a really cool idea, I don't think we've even considered this before. If you have information about how to get this kind of thing going, please get in touch! (My email is my hn username at cern.ch)

<comment><USER8> I've not been involved with SoC myself, but check out the website: [https://developers.google.com/open- source/gsoc/](https://developers.google.com/open-source/gsoc/)

Unfortunately the deadline for this summer has already passed.

</comment></comment></comment></comment></comment></comment><comment><USER10> From the paper: "[UHECR air shower] can be detected via [...] radio and acoustic signatures"

Does this mean that the particles have so much energy you could _HEAR_ the effects of them hitting the atmosphere?</comment>


OpenBSD Founder Calling for LLVM to Face a Cataclysm Over Its Re-Licensing - <AUTHOR> http://www.phoronix.com/scan.php?page=news_item&px=LLVM-License-Theo-de-Raadt <comment><USER2> Awkward....just as they imported LLVM [https://marc.info/?l=openbsd- cvs&m=147294297501630&w=2](https://marc.info/?l=openbsd- cvs&m=147294297501630&w=2)</comment>


Show HN: Dungeon Map Doodler – Free online map drawing tool - <AUTHOR> https://dungeonmapdoodler.com/ <comment><AUTHOR> Hey everyone, this is a project I've been working on for a little while now, it's a map drawing tool for tabletop role playing games like D&D, ShadowRun, etc. It's still in development, but has quite a few features already, most recently adding support for importing randomly generated maps from [https://donjon.bin.sh/d20/dungeon/](https://donjon.bin.sh/d20/dungeon/) and supporting publishing your completed maps to [https://fictionalmaps.com](https://fictionalmaps.com).

It's made entirely in html and pure javascript, running completely client side. It also has support as a progressive web app with offline support if you want to use it on the go. I'd love to hear what you all think about it! New bug fixes and features are frequently being added

<comment><USER2> i just played with it a bit and it's kind of awesome! It takes like 5 min to get the hang of it. I didn't notice until I came back here about publishing completed maps, that's great too. Passed along to my (many) game playing friends. If you decided to open source it I would join on for sure.

Why is the hallway tool called "snap to grid"? That was the one I couldn't figure out how to get back to because it's a non-intuitive name imo. When I went back in just now and restarted doodling, I saw that was the tool highlighted.

Also, the way the wall tool works is harder to use than the way the "hallway" aka "snap to grid" tool works, imo the latter is more intuitive.

Just some thoughts! Awesome work!

<comment><AUTHOR> Thanks for the feedback! I find it interesting you call it a hallway tool, I've never heard anybody refer to it that way before. When I first started, I had the free form drawing, and loads of people were requesting snap to grid options, so I added that as its own tool cause it had a few options specific to it. I personally use it to draw entire maps, as I often find it quicker to fill in a room than switching to the room tool and back. That's how I ended up with that name, and why I feel something like hallway is a little bit too specific for what it does.

I based the wall tool off of the line tool, since I assumed straight walls are the most desirable for people. How would you suggest making it work more similar to the snap to grid tool?

Thanks again!

</comment></comment></comment><comment><USER3> Reminds me of Dungeon Scrawl: [https://dungeonscrawl.com/](https://dungeonscrawl.com/)

As a DM, thanks for all these tools! Glad to have a variety of tools to use.

<comment><AUTHOR> Funny enough, I think the two of us started our projects on the exact same day, or at least first posted on Twitter, haha. He's doing some really cool stuff too!

<comment><USER4> I like both, but I'll probably 'move forward' with whichever one has masking working in a non-obtuse way first. With dungeon scrawler there is a pre-set that uses masks, but I've completely failed to figure out how to set it up on my own. I'd be willing to pay one-time fees to unlock art packs or other content to support the creators. But the dungeon fog style of wanting me to pay monthly... just... no.

<comment><AUTHOR> In this context, you mean masking to hide parts of the map from player? The crosshatching effect on my maps (which can be changed to all sorts of different styles) is created using a mask, so I just wanted to clarify.

If that's what you're going for, there isn't a super obvious way to do it in my software yet, but after making your map, you could add a new layer, switch to the Hatching Tool, choose solid black hatching, or any other solid image and draw over any parts you want to hide. Then to uncover it, just use the erase tool with all but the hatching checkbox selected, and it'll unveil the parts of your map underneath.

If you were thinking of something else, let me know and I'll answer as best I can!

</comment></comment></comment></comment><comment><USER5> Adding to my collection of D&D tools:

• [Dice For the Dice Gods: A D&D 5e Resource Compendium]([https://www.otherworldlyincantations.com/mastery/#1543209246...](https://www.otherworldlyincantations.com/mastery/#1543209246837-e72acb6f-9895))

• [Adventurekeep - A toolkit for dungeon masters]([https://adventurekeep.com/](https://adventurekeep.com/))

• [5etools]([https://5e.tools/](https://5e.tools/))

• [donjon; RPG Tools]([https://donjon.bin.sh/](https://donjon.bin.sh/))

• [One Page Dungeon by watabou]([https://watabou.itch.io/one-page- dungeon](https://watabou.itch.io/one-page-dungeon))

• [Medieval Fantasy City Generator by watabou]([https://watabou.itch.io/medieval-fantasy-city- generator](https://watabou.itch.io/medieval-fantasy-city-generator))

• [Azgaar's Fantasy Map Generator]([https://azgaar.github.io/Fantasy-Map- Generator/](https://azgaar.github.io/Fantasy-Map-Generator/))

• [Inkarnate - Create Fantasy Maps Online]([https://inkarnate.com/](https://inkarnate.com/))

• [Dungeon Scrawl]([https://dungeonscrawl.com/scrawl/](https://dungeonscrawl.com/scrawl/))

• [Dungeon Map Doodler]([https://dungeonmapdoodler.com/draw/#](https://dungeonmapdoodler.com/draw/#))

• [Dungeondraft]([https://dungeondraft.net/](https://dungeondraft.net/))

</comment><comment><USER6> Very cool! Any chance of Save-As-SVG?

Even if not, there could be some cool potential for integration with my project, Togetherness Table: [https://www.1kfa.com/table](https://www.1kfa.com/table) [https://github.com/sjbrown/togetherness](https://github.com/sjbrown/togetherness)

<comment><AUTHOR> Unfortunately no, it's all raster based in the backend, I haven't yet figured out a way that I could convert it into a legitimate vector file. That's a pretty cool looking project! I'll have to check it out more later

<comment><USER7> imagetracerjs might work:

[https://github.com/jankovicsandras/imagetracerjs](https://github.com/jankovicsandras/imagetracerjs)

</comment></comment></comment><comment><USER8> I like how clear, and easy it is to try it out. Big "DOODLE NOW" button right in the middle of the landing page. In two clicks I've already created a (tiny) dungeon.

</comment><comment><USER9> First of all, great project! I love this kind of tool and I bookmarked it because I could definitely see myself using this.

Some feedback: you need undo capability. It's quite common to make a mistake or change your mind about something and reflexively hit cmd-z to undo it. Along those lines, you need a "select" tool to click on things so that you can move or delete them after they are added to the map. Other than that it looks promising and I hope you continue development!

<comment><AUTHOR> Thanks, glad you liked it! Undo/redo is definitely there already. The arrow buttons in the top left near the zoom buttons will do that, as well as Ctrl Z for undo and Ctrl Shift Z/Ctrl Y for redo. I totally forgot that Macs use Cmd for most shortcuts, I should be able to add that in as well, thanks for letting me know!

That being said, the undo and redo currently only handles the drawing tools, text and stamps can be deleted their own ways, but that's definitely on the todo list.

</comment></comment><comment><USER10> Just wanted to say I got a real good laugh out of `draw/dmd.js:9`. It's the same verbatim array swap algorithm from Stack Overflow [0] I used at work today.

[0] [https://stackoverflow.com/questions/872310/javascript- swap-a...](https://stackoverflow.com/questions/872310/javascript-swap-array- elements)

</comment><comment><USER11> Minor site design feedback: I initially missed that I needed to scroll down, since the splash is sized exactly to viewport height. I even clicked "DUNGEON MAP DOODLER" text reflexively because I thought it might be a hyperlink.

Perhaps move the "DOODLE NOW!" button into the center of the splash.

<comment><AUTHOR> That's a good idea, I whipped up the website pretty quickly and haven't spent too much time reviewing it since, that's definitely something worth doing though!

</comment></comment><comment><USER12> This is really well-done. Very polished, and all of the drawing tools work as my mental model thought they might.

Kudos!

</comment><comment><USER13> This is very cool! Do you think you could add a feature to move around npc/character pieces? Even if they were just coloured blocks, that's all I need now to run a basic DnD session. Add some dice too and I can easily run a Zoom DnD session.

<comment><AUTHOR> Thanks! The original goal of this was to make printable maps really easily, so I haven't focused too much on interactive stuff like character tokens or fog of war. However, you can easily add your own stamps (there's a button at the end of the list, or if you click the current stamp, there's a big button on the popup), and stamps are easy to drag around, so that could be a solution for you there.

In regards to the dice, do you mean an actual dice roller, or just stamps of different dice?

<comment><USER13> I meant a dice roller, but I understand your intention now. Thanks for the tip about the stamps, I'll give it a shot!

<comment><AUTHOR> Well, as with all projects, the scope has creeped a little bit already, so I won't say never to that! It's definitely something I could be open to adding in the future, if I can think of a good way to fit it in with this tool.

</comment></comment></comment></comment><comment><USER14> Ah, this is exactly how I feel like this tool should be! I found the UX on other similar apps to be confusing or lacking what I felt were fairly necessary rudimentary features.

Thanks for building this tool!

<comment><AUTHOR> Thanks for the feedback! I've been trying really hard to keep the interface as simple and intuitive as possible, so it means a lot to hear that!

<comment><USER14> Ah, I found one thing that's kind of bugging me - the text tool.

It seems the text is not layer-specific. It would be nice if it was so I could have a "notes" layer that I can turn on and off for exporting two different images - one for players and one for the DM.

The text tool also seems to create text well above where I actually clicked. Ideally I would imagine the point that I click to be the top-left-most corner of the text box.

<comment><AUTHOR> Yeah, the text tool is a bit lacking at the moment, and I think the public release still has a small bug with where the text gets placed down when clicking.

That's a really good use case for the layer specific text which I hadn't considered, thanks for bringing that up! I think the text tool is the next thing I'm going to be giving a bit of love to, it's definitely a bit quirky in how it works right now

</comment></comment></comment></comment><comment><USER15> This is so cool - congrats! Spent an inordinate amount of time playing with this given that I've never actually played table-top games...

</comment><comment><USER16> Awesome! Thank you for sharing! Making quick maps on the fly is a bit of a weakness of mine as a DM so I always pre-prep.

</comment><comment><USER17> Loved it! Brings back fond memories of playing Zelda as a child.

</comment><comment><USER18> Wow this is awesome! Keep up the good work!

</comment><comment><USER19> Extremely cool! Well done!</comment>


Srsly WTF? Radio Shack Offers Free Gun With Dish Network - <AUTHOR> http://www.centernetworks.com/dish-network-free-gun-montana-radio-shack

<comment><USER2> Mid nineties there was a bank in Boulder CO offering guns for signup or some event. I forget the details, I saw it on their sign outside.</comment>