PC Tools Firewall Plus 6
Powerful firewall capable of providing excellent protection.
Comodo Firewall (standalone)
Long been considered one of the best free firewall tools available.
ZoneAlarm Free Firewall
Provides the best overall firewall protection for advanced users.
Online Armor Free
All of the normal features of a firewall and more.
Ashampoo FireWall Free
Very easy to use and navigate. For intermediate users.
Peerblock
Provides control over who your computer “talks” to online by blocking known bad addresses.
TinyWall
A great free firewall solution that puts you in charge of whitelisting applications in a non-intrusive manner.