The good part is you can do it yourself without GitHub (which, after the downtime, could come into the equation quite easily):

  -- Remote machine, or SSH port forwarded machine --
    > adduser git (you either add pusher/puller's ssh pubkeys to its 
      authorized_hosts, or use a shared password)
    > su git
    > cd ~
    > git init --bare myproject.git

  -- Your local repo --
    > git remote add <name> git@aforementionedmachine:myproject.git 
    > git push <name>

Setting up a git repo for confidential pushing and pulling is quite easy.