I'm all for having a hardcore clan night, whether it be entering in tournaments, challenging other clans or just playing against ourselves.
Pick a regular night or 2 a week and lets do it. I thought that was the point of being in the 'hardcore' clan.
Cheapy, save yourself the money on a mac mini and just get this for your current macbook:
http://www.nullriver.com/products/medialink
It lets you stream movies, music or pictures straight from the hard drive on your computer to your PS3 over your home network. Your macbook hard drive shows up...
Check out crossfire: http://www.codeweavers.com/products/cxgames/
You can play just about any steam game no problem and quite a few more. I've been playing TF2 and portal on my 2 year old MBP no problem.