Hey rogue77, I don't know about the xboxes, but I am networking wirelessly very smoothely using a simple Linksys wireless 802.11g router. My room mate and I are both using new Powerbooks while a student above us is using his Dell laptop.
We didn't do anything tricky- just wired the edu connection from the wall into the router, then configured the router to automatically assign IPs to our systems, and we were good to go in about 5 minutes!
Go ahead and give it a try when you can, and let me know if you have any problems, I'd be happy to help.