Yeah, I read that thread but was having trouble finding any of them for cheap. A couple of them were only $20 but they were mini-pci and I'm using a desktop.
Anyways, I managed to find a $20 card from eBay should work for me... (It's on the official hardware compatibility list anyways...)
Thanks for the help though!
(By the way, do you use pfSense, m0n0wall, or smoothwall?)