OnionCat is a VPN-adapter which allows to connect two or more computers or networks through VPN-tunnels. It is designed to use the anonymization networks Tor or I2P as its transport, hence, it provides location-based anonymity and surveillance protection while still creating tunnel end points with private unique IP addresses.
Please have a look at onioncat.org for more information.
With 9th of January 2018 the source repository was moved to Github.