I actually ran into a very similar problem this weekend. I ended up using gitolite with post-commit hooks that checked out the repo to a directory served by ng

I actually ran into a very similar problem this weekend. I ended up using gitolite with post-commit hooks that checked out the repo to a directory served by nginx. It ends up taking up a lot more space than Mike's solution, but has fewer moving pieces, assuming you're already running nginx. Additionally you can use it to set up some fancy rules, like the "production" branch push to a special place, allowing users to create their own repos, and fine-grained access controls via gitolite.