I've put up an experimental git repository for Penn.
Get it via: git clone http://download.pennmush.org/Repos/pennmush.git
Handy for local hackers, since you can create local branches for custom stuff and keep up to date. I think. Branches and git and I haven't gotten along in the past. Please don't ask me how to use it.
It should sync with the master subversion repository on googlecode every couple of hours.
Branches and tags that exist in SVN aren't working right yet; I think it might be an issue between the git-svn created private master, and the bare copy that's being exported on the web server. I don't know enough about git to tell.
It's a work in progress. Play with it, but don't rely too much on it for now. There's kinks to work out.