I don't think this is such a good idea. First of all, designing a catch system that isn't terrible is a lot of work -- it doesn't really make sense for most dev

I don't think this is such a good idea. First of all, designing a catch system that isn't terrible is a lot of work -- it doesn't really make sense for most dev teams to take it on when there are so many pre-built solutions out there. Second, dealing with proprietary captcha systems isn't actually that hard -- you can throw pretty much anything at anti-captcha.com.