See also:
Best VGM 51 - http://www.youtube.com/watch?v=GKFwm2NSJdc
Best VGM 488 - http://www.youtube.com/watch?v=eyhLabJvb2M
A collection of my favorite videogame music. Note that most of them are from games I played so I might miss some great ones from games I never played.
Gamecube
Paper Mario 2 The Thousand Year Door (2004)
Event Battle
Yoshito Hirano & Yuka Tsujiyoko
