OSS Web-based File Management?
I use this all the time, and it works relatively well.
Version 1.1 had "broken" support for some clients and the revision mecahnics left a lot to be desired: If you modified a file under Windows WebDAV support, anyhow, it would see it as a "delete file", "create new file" pair. You can still go back a version and get the previous version, but the file history is broken. If you log in to the repo with a username, it does track who you are.
Version 1.2 supposedly fixes all this so it "just works". I have not had time to upgrade yet. Modifications are logged as modifications, etc.