Here's one I just built. It's one ugly ass machine but it kicks ass on games and just about everything else. I built it out of parts you can order on the net.
Thermaltake Xaser case and 465 watt PS
Soundblaster Audigy 2 Platinum
Radeon 9500 Pro
Intel PEBT2 motherboard
512MB DDR333 RAM
P4 2.53 Ghz
80 GB Maxtor hard drive
Yamaha CD-RW F1
18 inch NEC LCD
Still need to clean up the wires and replace the white face plate of the Soundblaster Live Drive with a black one. Unfortunately I'm stuck with the white CDRW drive. Also going to get the HDTV connector for the Radeon video card so I can play games in 720P on the big screen TV.
I'll never buy a premade one again after building my own.
The green alien fetus in the background was not included.