I was just looking at Drew Houston's application from Summer 2007 and saw that they asked applicants to keep all responses under 120 words. Is this still the case?
Try to keep your responses succinct. I like how Garry Tan put it in this blog post (http://blog.garrytan.com/super-last-minute-advice-for-s): Answers should be "crisp and articulate, and to the point. One way to do this is to write every last idea down -- write copiously. Then edit. Edit mercilessly until there is not a single word you could remove without losing significant meaning."
Very helpful, thanks! I definitely have the "write copiously part" down. I'm going to go pick up some red pens...