i have a Cube for the same reason i have every Nintendo machine - the Legend of Zelda. however, i really don't use it very often, my games of choice tend to be on the Xbox first, then the PS2, and my beloved Dreamcast.
that doesn't mean that there are no games for the Cube, and i'd like to hear about your favorites. i happened to really enjoy Summoner 2 - it wasn't perfect, and i have some issues with the ending (no spoilers, email me if you're curious), but i played it through, was totally hooked the whole time, and would recommend it to others.
it's got rpg (action, not turn-based), hack-and-slash, magic, some puzzling, and exploring/ collecting elements. i had a hard time getting past the first screen - what me, read the manual? - but once into it, i had a blast, and for a long time, too. there's a lot more that i liked, i'm sure, maybe someone with a better memory will fill in the blanks!
let's hear about your favorites and why they're your favorites! details, please...