Ask HN: Where to run away to crank out my web app?

I live in San Francisco, and I'm thinking about taking a month off from my very busy day job to work on finishing the first version of my startup's web app. I'd like to find somewhere where I will be able to work with less distraction on making magic happen. Has anyone here ever done something like this? I know lots of writers run away to a cabin in the woods to focus --- I'm looking for the tech startup version of this kind of thing.

Extra points given for places with reasonably fast Internet access, and being able to find accommodations that won't be much more than my current rent (about $2,500 for a 1-bedroom).