[Segageo64]

Routers are nice to network multiple P.C.'s together and still be able to run them independently, no need for a main system. If you have a high speed ISP you can run multiple computers from a single connection and assign them all different ISP addresses (Free). Nice for playing multiplay games against others at home or groups of people at home against others on the net.
If you get a wireless router (about $100) it will come in handy if you own a laptop.
In my opinion a router is a MUST HAVE if you have cable or more than likely DSL (like you) internet and more than one P.C.. Get one with a high speed transfer rate so you can tranfer files from one P.C. to another quickly when needed. Hope that helps.