Comodo Firewall

Product: Comodo Firewall v5.4
Company: Comodo 
Website: www.comodo.com
Type: Free
Requirements: Windows XP/Vista/7

Comodo´s free Firewall keeps viruses, malware, worms, Trojans, hackers and other Internet threats from accessing and harming your PC. Using an exclusive white-list of over 15 million known PC-safe files, Comodo Firewall blocks unknown viruses before they can even install. The software also features real time traffic monitoring, informative alerts and is simplicity itself to install and use. Comodo Firewall is completely free for life.