http://ycombinator.com/ideas.html Y Combinator’s “Ideas We’d Like to Fund.” Some great stuff here. “25. A Craigslist competitor. Craiglist is ambivalent about being a business. This is both a strength and a weakness. If you focus on the areas where it’s a weakness, you may find there are better ways to solve some of the problems Craigslist solves.” 20:59