zonealarm free firewall

Group-based basic PF firewall frontend.

Front-end for the built-in PF firewall in OS X 10.7 or later.

Lightweight and fast application firewall.

View, understand and react to access attempts detected by your firewall

The Mac's first firewall keeps getting better!

NetMine by ProteMac is a firewall for your Mac computer running OS X

Send email from behind any firewall, no matter how restrictive it is.