I thought I'd share this with everyone here as it seems pretty cool. Xlink Kai is a software that you can download for either your Mac or PC that enables you to play network compatible games, online for free. It works with Gamecube, Xbox, Playstaion 2, 360, and PSP games at the moment. If you already have a router at your home, setting this up seems pretty simple. Just download the program, foward some ports and, "lrn2ply' online with your game of choice! I was able to get this running with Armored Core:Last Raven and its pretty cool.
The only downside is that there seems to be some connectivity issues. I can usually play games with people in my region with not too many problems. But as my opponents locations lay farther from me, then thats where problems connecting/staying connected start to occur. Also, its easily effected by background programs like AIM or Internet Explorer. But being that its free, I guess you can't complain.