Call me a cynic, but I find it much easier to start with a blank slate. It may be slower to begin with and I may end up missing out a few edge cases, but I find that I end up painting myself into a corner with css frameworks as the project grows.
Zurb Foundation is a very nice responsive framework. I'm both happy to see it here on HN and sorry to find that the post has done a terrible job at capturing readers' attention during the first 5 seconds.
