Packet Filter log parser
An IPv4 Packet Filter with Network Address Translation capabilities.
DNS Blacklist Packet Filter is a Linux netfilter client that decides whether to accept or drop packets.
Drawbridge is a firewall package developed at Texas A&M University and designed with a large academic environment in mind.
ppfilter is a personal firewall for Mac OS X
SONaFR is a small system based upon OpenBSD 4.1 with router, NAT, and firewall capabilities that fits on one floppy.
Frickin PPTP Proxy is a fast PPTP proxy for any BSD system with the OpenBSD packet filter installed.