All of my git repos live in a subdirectory of my dropbox as-is. I also compulsively push to remote. I also use Time Machine. I also rsync my home directory to an external drive in case Time Machine implodes. I also rsync my home directory to a server in another hemisphere.

Come at me, bro.

Pushing to dropbox is a very common part of my workflow: https://github.com/rpetrich/git-dropbox It's not strictly safe to use from multiple machines, but as a simple backup it's very convenient.