PC Games: Beyond Good & Evil (Steam), N, Audiosurf (Steam, of course!), Bullet Candy (Steam), Lumines (you guessed it, Steam!), Trackmania Nations Forever (Steam), ROM Check Fail
Wii Games: Super Mario Galaxy, Super Smash Bros. Brawl (4897-5619-0801 Friend Code), Zelda: Ocarina of Time (VC), Starfox 64 (VC), MP3: Corruption, Guitar Hero 3 (I don't know my friend code for that one), and others! See mapwii.com (Wii #: 6195-3114-5941-7900).
DS Games: MarioKart DS (Don't know that code either), Zelda: Phantom Hourglass (Or that one; too many codes!) Contra 4, and many more!
PS2 Games: R&C 2-4, Burnout 3 & Revenge, Okami, Guitar Hero, The Adventures of Cookie and Cream, DDR Extreme (which I DON'T PLAY, really!), and games I don't care to mention.
PSN ID: PSWii2008 (P, S, & W all in caps)
MGO Game ID: dawimp523
If you haven't heard, N+ is coming out on XBLA tomorrow. I just downloaded the original N Monday, and it's one of the best games I've ever played! In high school, I saw people playing this during class, and I would wonder what all the fuss was about, and now I know. It's very challenging, similar to Contra, but very rewarding as well. I've never played a game that helps build your skill level so much, and gives you a sense of accomplishment. If you're new to this, you'll know what I'm talking about if you get N+, on XBox Live tomorrow, and coming soon to the DS and the PSP!
My advice to newcomers trying this out is be prepared to die. You will die a lot, and you might want to kill yourself if it gets too hard (you can do it with one button, but use it only when necessary!). But the payoff is worth it!