How prevalent are coin attacks with botique altcoins? I have deployed several altcoins using various PoW algorithms on my LAN for my buddies and I to mine/learn from. We ultimately want to go the distance of deploying an altcoin to the world, writing the white paper, doing the leg work of maintaining it and getting it listed on an exchange. 

I have a fear that since our incredibly slim budget has limited us to a very small amount of computational power with which to develop these altcoins (at least initially) that if/when we go the distance of releasing a fully functioning altcoin we will be swiftly crashed by someone with a cabinet full of ASICs and a love of trolling. 

I guess my question(s) are how common is this and what is the least expensive but effective way of preventing it. Please don't destroy my dreams, I understand making a coin that ever ends up worth anything is highly unlikely, I am asking for technical advice relative to the issue at hand, not to be told that having a coin of value with a small development team and little capital investment is impossible.

Thanks! 


Schwifty
If you'd like to be absolutely sure that some malicious miner won't attack your coin, you could hard-code in a set of 'approved' miners (ie, your miners). Doing so greatly undermines some of the core concepts of a cryptocurrency though (open, permissionless system, etc), so that probably isn't a good option by most measures.

So then, what is the best option? 

Many coins choose to employ an 'ASIC-resistant' algorithm, with the goal of preventing ASIC-wielding miners controlling their network. Instead, the idea is that GPU (and perhaps CPU) miners will be the ones securing the network, and many people argue that the the distribution and economies of scale involved in GPU mining are better-suited to create a decentralized network.

However, in practice we've seen that perhaps no algorithm is ASIC-proof. In fact, an algorithm that is extremely difficult to build an ASIC for may just concentrate mining power even further, as very few people will have the skills and resources to create an ASIC for such an algorithm. Such people could thus easily control the majority of hashpower on a network, once they have built some ASIC miners. 

For a more in-depth look at this issue, check out this article written by David Vorick (a SiaCoin dev). 

It is worth noting though: nobody is going to invest the resources to invent an ASIC that attacks a very small coin. There would be no economic incentive to do so, this problem only becomes apparent once the network has grown and is storing a worthwhile amount of value. (Keep in mind though, if you choose an algorithm also employed by a larger chain, then such ASICs might already exist).

Trolling aside, it is also worth noting that it is not necessarily in a miner's economic interest to attack your coin. If a miner owns some ASICs, and can make money by mining with them, then there is perhaps a substantial opportunity cost involved in instead using the ASICs to attack your chain. This incentive helps keep miners 'honest', in that they will benefit more by using their hashpower to secure a chain, rather than attack a chain.