git-tfs is an two-way bridge between TFS and git, similar to git-svn.

Right now, only fetching works, and it's pretty dumb (it refetches everything
every time and doesn't do any branch tracking at all). Eventually, it will do
the tracking thing (or at least set up the master branch when you do a clone or
the first fetch), and it will be able to commit to TFS, etc.

Also, I've only tried it out with the TFS 2008 client libraries. I intend to
make this work transparently with TFS 2005 or the codeplex client libs at
some point.

Here's how to use it:

# git init
# git tfs init http://tfs:8080 $/some_project
# git tfs fetch
(This will take a while, and currently doesn't output anything.)
# git tfs merge tfs/default

Like I said, eventually fetch will be better, there will be rebase, and there
will be commit.