Now, what I find really fascinating is: if you assume that even only 0.1% of these user generated levels is actually fun to play, this still leaves you with 1.000 enjoyable levels! Even if you only play a hundred of those only for 10 minutes, you have increased the time you spent playing this game by 16 hours (which is more than some games deliver out of the box).

Obviously, the problem is finding those 0.1% – market for a new kind of search engine? Are there cross-game UGC search engines already available?