I would go with a switch. If you have only one IP address, then you should go with a router/switch all-in-one thingie. Switches, if connected to a 10/100 NIC will alow you to connect two computers in 100 full-duplex mode (effectively 200mbs, 100 send and 100 receive). I notice a difference in speed when using just two computers between a switch and a hub, especially when both PC's are in heavy use (downloads, games).