Zonealarm is good but i use Agintum "OUTPOST" firewall, it has a free version v 1.0 even this firewall is very impressive, it can tailor make each and every individual attempt to connections, a single software can be permitted one site while at the same time the same software can be stopped contacting any other site as pre your choice this feature i found very unique, may be present in costly firwalls but definately not in free firewalls... in my opinion outpost is the best....please excuse my difference in opinion