I am playing a few games right now:
Mario galaxy
zelda wind waker
zelda ocarina of time
there are also game that I just play all the time, but not consistently
Smash Bros Brawl
Guitar hero 5
FIFA 06 (GC) I know this is a failure on my part, but I just never get around to buying the next ones. they're all the same to me, except for the rosters (I fix those myself)