I'm sure that there are at least a few other math junkies on this board... if you are one, you'll probably know what I mean
Anyway, I just thought I'd share http://www.artofproblemsolving.com with anyone that's interested. They sell books which are quite good for learning "contest" math, and just math stuff in general... and there are problems posted on the boards for you to solve.
No, I'm not being paid.