A newer version of Comodo Firewall is available.Or, Learn More About Comodo Firewall
Full user review
"Best firewall known on the web."
This beats zone alarm and is way better then windows firewall. It has advanced HIPS which almost no other firewalls don't have. It's defense+ is excellent to block unwanted programs using its cloud services.
6.0 should come out soon. 5.0 has been out since late 2009. Just do not use windows firewall with this. Otherwise, you will experience systems crashes and slow downs.
Pretty much said all I need to above. #1 firewall recommended.