DansGuardian

From Kathmann Labs

[edit] DansGuardian

Dansguardian is an open source software project that provides web content filtering. It uses a variety of methods including phrase matching, PICS filtering, and URL filtering (lists). It runs on top of linux in conjunction with squid cache proxy server, another open source software package for web proxying. Along with just content filtering, it will allow you to set up filters to block certain extensions from being downloaded (like EXE, MP3, VBS, etc) which could be useful for stopping viruses or pirating. There are several ways to allow people, websites, and computers to either be blocked or allowed, allowing you to customize who gets blocked and who doesn't.

Open Source Web Content Filtering Project