Cool. Set it up with Windows or buy an extra Mac Monitor.
Yep. I got my 2.0 GHz eMachines pretty darn cheap ($750). 512 MB RAM, 160 GB hard drive, and it can play CDs, DVDs, and all of that stuff (watched "Godzilla, Mothra, and King Ghidorah: Giant Monsters All-Out Attack" last night on it - the BEST Godzilla flick I have seen).
Run a KVM switch and use only one keyboard, mouse and monitor.