VSTrac is a Visual Studio addin which integrates Trac functionality into Visual Studio 2005 and 2008. It's main function is to facilitate management of tickets from within Visual Studio...
Prophet is a new kind of database that offers peer-to-peer opportunistic replication (it's basically like a database version of the Sync framework). It's a very lightweight semi-relational database.
SD (Simple Defects) is a bug tracking tool based on Prophet that is not-only peer-to-peer, but it syncs with other bug tracking tools!