Josh – I think a few of the truely hardcore hack their Linksys routers’ firmware, but for you and me there isn’t much we can do.
Switches provide a way to “split” the network connection, but since Comcast only gives us one IP address that address needs to be shared between computers. NAT routers typically include a 4 or 8 port switch, which is what you plug your computers into.
With IPv6 people would no longer need expensive NAT routers and could go with cheaper switches.