XKCD Color Quiz
This quiz was created from the XKCD color survey that was done quite a few months ago. If you don't know about this survey, I would highly suggest that you go to xkcd.com and click the News/Blag link, then scroll down to where it talks about the color survey results so you can get some more info. This quiz contains over 900 different possible colors conducted from that said survey, randomly generating over 7 stages with increasing difficulty (at least in the amount of colors). Overall though, it's not THAT hard as I'm colorblind and even I managed to score decently...1/100 times.