Not sure if this is related to this thread or has been brought up before, but regarding mass multiplayer servers, has anyone ever considered using the Bit Torrent concept for multiplayer games? That way you could have a ton of people, and each time more people joined the bandwidth would increase, not decrease.
Of course, this would leave the thing open to hackers, who might exploit the synchronization of the whole thing (this is the most important part, after all). Or could you get it to synch up in the first place?
Any ideas?
-Franks