Eddie Edwards writes "This story over at Gamasutra details how Worlds.com have been awarded US patent 6,219,045 for - well, for more-or-less exactly the client-server architecture used in Quake. As the article says, "the company believes the patent may apply to currently in-use multi-user games" (!) and Worlds.com "will also review other 3D sites who may be using [their] technology to ensure [they] are fully compensated". " Of course, Worlds.com will prolly get squashed on the prior art issue - but wow. From what I can see, IANAL, it's not so much Quake-like games, but more like 3D chat-game-type environment.