git-annex can communicate over the Tor network. This allows direct
communication between git-annex repositories, no matter where they are
located.

A git remote using tor has an url that looks like
`tor-annex::2lssjzicvsxkdc2v.onion:19984`

To set this up, use [[git-annex-enable-tor]] and [[git-annex-p2p]],
and run [[git-annex-remotedaemon]] to serve the Tor hidden service.
It's explained in detail in [[tips/peer_to_peer_network_with_tor]].
