back when I first got my DSL connection, everyone told me a router was a must-have item, because of the hardware firewall.

But now with windows xp service pack 2's firewall greatly enhanced and with free software like zonealarm, is the router still a must-have item for broadband users?

I own a router and so I use it, but I'm asking because my friend just got DSL and he does not have a router, and the only reason to buy one would be for the firewall since he only has 1 computer he doesn't need it for routing purposes.

So should I recommend he spend the money on one or is he pretty safe with zonealarm?