Cable Modem r00lz!
The CPU on top is an AST/Bravo 486/50, and acts as my Internet server. It runs the (excellent!) Sygate software on Windows NT 4.0, and allows me to share one Time-Warner Road Runner cable modem account among the other 4 nodes on the LAN.
I can't praise the Sygate software enough. If you're ever in need of modem/Internet sharing software, I recommend it highly. Yes, Microsoft now bundles software with the new version of Win98 which will do the same thing. But it's a royal pain to use, much less set up, whereas Sygate is as easy as pie in both regards. It's well worth the price!