I work on Startup School at YC. We're excited to launch our second-ever build sprint. You can think of a build sprint as sort of like a 4-week hackathon, with regularly scheduled checkpoints and a community of other folks all working on their ideas at the same time. If you’re looking for an excuse to take the plunge and start work on a startup or side project, this is a great opportunity to do that.
(Note: I’m traveling today so won’t be as active in the comments as I’d like, but will pop in to answer any questions as often as I can!)