monotone is a distributed version control system with a flat peer model, cryptographic version naming, meta-data certificates, decentralized authority, and overlapping branches.
TracMonotone is a plugin for Trac that allows a Trac project to use a Monotone instead of a Subversion repository. The plugin enables you to browse your project's sourcecode, view changesets, etc.
Like it or not, the distributed revision control model is here to stay. Brian Fitzpatrick, a Subversion and Apache developer, told a group of us Purdue students that SVN will indeed be getting distributed features similar to "the Mercurial model." Man