Prometheus

Prometheus is a configuration tool for Mac OS X system's firewall. It's written in Perl and with some little changes it could also be used on FreeBSD systems.

It is a script that could be executed by a graphical user interface (GUI), or directly by the command shell (Terminal) and it requires administrator's privileges to work on system's directories, where it configures the scripts and the files necessary for firewall's correct working. It's really versatile, in fact it allows unexpert users to execute a step-by-step configuration by a series of simple questions and expert users to set manually a list of firewall rules, checking the syntax.