Tund (tunneling daemon) establishes a reverse SSH tunnel from some computer to an internet accessible computer to your own. It's usefull for machines behind a NAT you'd like to have a tunnel to and you don't want to create firewall forwards or deal with dns.
This project is inspired from https://raw.githubusercontent.com/aphyr/tund. The deamonization code is used from http://www.jejik.com/articles/2007/02/a_simple_unix_linux_daemon_in_python/ with some small changes.