ATI 4890, E8500, 4 GB, nothing special. still rocking Promedia 5.1's that won't die.
Now that I'm graduating in less than a month, I'll be able to get back to the games I love, but basically:
*Left 4 Dead
*Left 4 Dead 2
*Team Fortress 2
*Diablo 2
*Quake Live
My list of owned games would be a mile long, but those listed are the ones I've played in the last 6 months. My preference goes FPS first, then racing, RPG, and RTS in no particular order after that. I play CSS, but usually only at LAN parties. I'm a die-hard Quake fan, and would be playing Quake 1 CTF (14 year old game) today if there were active servers still around.
XBox 360...I have the usuals, Assassin's Creed, Rock Band 1 and 2 (I drum on expert, probably about 60% of the songs...I say that not to brag, cause I know it's not much, but in case others play), Forza 2, etc. No first person shooters on the 360...FPSs have no place on consoles, I'm sorry if that hurts someone's feelings.