I have a dual core Shuttle system I could probably part with. Comes with the 22" monitor with no dead pixels
Shuttle SD32G2B
Intel Core Duo E6300
1gb Muskin Enhanced Performance
74gb Raptor
Lite-On 16x DVD/RW
22" Acer AL2223W
It doesnt have a high end gaming card in it right now cause I'm not a gamer, but that could be added pretty easy, it uses a pci-e slot
If you need a ton of storage space I could also include the external hard drive unit on top of the Shuttle. It has four 400gb Seagate hard drives in combined mode to make a single 1.6tb drive. I use it for storing/backing up my movie collection. It has about 600 movies on it right now.
$800 for pc and 22" monitor
$1500 with the hard drives
Crappy pic, but you get an idea what it looks like:
I also have a MicroFly case with 400 watt power supply which is a little larger than the Shuttle. Right now it has a 1.3ghz AMD in it, but I could easily build it up to whatever specs you want.
It has windows on both sides and the top(which are still covered in the protective window stuff) and a handle on it to carry it to lan parties or whatever.