Diablo II is an awesome game... you must have gone mad playing it for that long....
Well... as for me. I would have to say that the only games I bought that were utter crap:
1: Frankenstein (GameBoy)
2: Supreme Snowboarding (PC - This is one of the few pc snowboard games available...)
3: The Sims (PC)
There are bound to be more... But I can't think of them right now...