Trac is a fantastic, world-dominating software project management and bug-tracking system written in Python. It integrates with Subversion and has a wiki and just works. Even the Rails guys use it. It’s possible that if Trac and Chuck Norris walked into a bar, only Trac would leave.
But unfortunately, the comment-spammers and wiki-spammers have noticed Trac and have been updating their scripts. Hence the 12,000 15,000 hits for “trac spam."