Aye, I enjoy a lot of the games on the 'cube. There is certainly a much greater level of competition involved with some of the games, like 1080 Avalanche or Mario Kart from the online community. Scoreboards are rife!
If you're into your driving games though, I thoroughly recommend you hunt down the official force feedback wheel and hook it up to Burnout 2. The game gets about 10 times better through the wonder of force feedback! Not only that, grab F-Zero GX too and it is like having the arcade machine in your home, using the FF wheel.
My poor little cube hasn't been off very much of late as I took delivery of R: Racing Evolution quite recently (well, about a month ago), which is another stunning title available on all the systems. I picked up the cube version because of the Pacman Vs. game that comes as a bonus -- such a funky little freebie which drips with pure multiplayer goodness, given a GBA and link cable and a few willing friends/family.
It doesn't get much better than this