Analyzing email account to try and predict/find signs of brain disease.

~adsense clone, crawl page, find top keywords, and for each advertiser (which has a catalog of up to 5M products) find best product and display as ad in a widget.

~smart ~ai in a complex game of pong (powerups, multiple balls with different speeds, dynamic net size, special abilites). it was a very complex if-else-if tree, but I was in 7th grade learning by myself with no home internet-connection