Another possibility is to get a router that has a built in NAT firewall. These are becoming very common and popular these days, and a 4-port ethernet router can be purchased for under 50$. Hardware firewalls are much more superior to software files in many ways, they don't 'freeze up', the firm ware is usually more secure, it doesn't require system cpu cycles or system memory, and it is usually faster as well. A NAT firewall will deny any incoming requests that were not preceded by an outgoing request. What this basically means is, if your computer did not ask for the information in the first place, NAT will deny it, and your computer will never even be bothered by the packet. NAT will block port scans, attempts to connect to 'most' torjans, any services that may be running on your box from being accessed by people not on your LAN (which would include NetBIOS), and other things like that.