A router is a pretty effective firewall. The main use for a hardware product specifically sold as a firewall is that it is configurable.
Yes, that's what I meant about setting up a LAN ( local area network )-- the new ones seem to filter out about 90% of the probes. I keep hearing about the Barracuda on the radio, which I take to be a dedicated, outboard firewall, but figured anything that doesn't mention price is probably, well, kinda pricey.