Somewhat in the same space, I saw an interesting stackoverflow post[1] about how to generically retrieve a single file from git. Apparently since git version 1.7.9.5, you can do this:
git archive --remote=ssh://host/pathto/repo.git HEAD README.md | tar xO
Though apparently support depends on how you're running git, and potentially some enabled server side options.
[1] https://stackoverflow.com/questions/1125476/retrieve-a-singl...