Well, I've been having horrid connection problems for months now at my dorm. Basically what happens is that I can connect to the network fine, but the data flow in and out is periodically interupted for a small amount of time (20-30 secs). Unfortunately, this is enough to cause the Steam connection to reset and kick me out of any games online. I've played with my adapter settings many times and that only produces a temporary fix (5-10 min). I've called the tech guys at my school twice and they haven't been much help. I've never had a problem with any other wireless network, just the network at my college. The network uses the Cisco NAC Agent for security purposes. I'm not sure if that would cause problems with Steam or not. Hell, I'm not even sure if its just a problem with Steam or my connection as a whole.
So, if anyone has any ideas, please spare me more raging at my computer...I'm sure my desk will appreciate the decrease in violent beatings.