Here is my gaming beast:

Athlon 64 3000+ (Clawhammer), 1 GB DDR400, Asus K8V Deluxe, Sapphire Radeon 9800 pro w/128 mb, SB Audigy 2 ZS, 120 GB Seagate Barracuda SATA HD, Plextor PX708a dvdr, Antec True430 psu, Antec P160 aluminum case, Logitech 5.1 surround sound, Logitech MX Duo w/MX700 mouse.
It runs win xp for now, which will change in a bit when i get a new 200 gig hd for anime,etc.