I didn't realize they even have LAN parties anymore.
OP, how do you find these people? Look them up on the local BBS?
Haha. My roommate and a few of my friends host LANs from time to time. 2 or 3 of them are "hardcore gamers" in that they play a lot of video games. Most have custom build desktop PCs with 24 inch and up screens. We're talking 5-6 fans inside each case, colored LED lights, 3-4 hard drives inside each case, etc etc.
I think its funny how many posts here are like "I didn't know LANs still existed." This is a joke I hear from PC gamers, "See Mac users don't even know what gaming is so that's why their computers can't play games."
The tide is really turning in favor of Macs at LANs, with graphics cards that hold their own and Valve's Steam software on Mac OS X. Of course a desktop PC still remains more powerful for gaming than a laptop, which is why at most LANs people come with huge desktop PCs.