DAXFi is a Python package that helps configure several different kinds of firewalls in a consistent way. The rules are described in XML. It comes with a Python package, useful to build other applications and includes some useful example programs.
CompactBSD is a powerful set of tools that allow you to build your own customized,
lightweight distribution of OpenBSD and then burn it onto
compact flash so that it can be run on an embedded PC platform such as FatPort's
FatPoint (www.fatport.com)