Humm, I have about 20 games for the gc as well. Do you have Eternal Darkness??? Awesome game. I think it is the game with the best use of surround sound. You can finish it in about 1 hour and half, but you got to finish it 3 times to get the real finish, and the most interesting mode is the green one (sanity)
A friend lend me that game and I had to buy it, even thought I had already finished it.
Now, you have 100PS games. I have about 100 Dreamcast games. and 1 PS2 game (Clock Tower 3)The Dreamcast had some awesome games like Soul Calibur, Dead or Alive 2 (I have the limited japanese version. Got it new from ebay at 65 $ . I love that game) San Francisco Rush 2049, Shenmue, Gaunlet Legends (with good graphics, not like in the N64) Powerstone to name some