I've just gotten an attractive job offer. I've been doing a lot of reading about negotiations, here on Stack Exchange and [elsewhere](http://www.kalzumeus.com/2012/01/23/salary-negotiation/). The general gist seems to be that it's silly to leave money on the table when you're in a strong bargaining position. The thing is, I don't care about money nearly as much as I do about vacation time. I would start at the standard (in the US...) 10 days per year, which seems like so little. I'd even be willing to take less money in exchange for more time off. 

* Is number of vacation days negotiable?
* What's my best strategy to get more time? What's the most I could reasonably ask for?
* What's a rough relationship between dollars and days than I can use to calibrate my requests? Or is there one at all?