Hypergrid
From OpenSimulator
The OpenSim Hypergrid
What is the hypergrid?
The hypergrid is an extension to opensim that allows you to link your regions to arbitrary opensims on the internet, and that supports seamless agent transfers among opensims. It can be used both in standalone mode and in grid mode. The hypergrid is effectively supporting the emergence of a Web of virtual worlds.
The basic idea for the hypergrid is that region/grid administrations can place hyperlinks on their map to hypergrided regions run by others. Once those hyperlinks are established, users interact with those regions in exactly the same way as they interact with local regions. Specifically, users can choose to teleport there. Once the user reaches the region behind the hyperlink, she is automatically interacting with a different virtual world without having to logout from the world where she came from, and while still having access to her inventory.
The hypergrid is currently a GForge project. Technically, it's implemented as a thin layer on top of the OpenSim core facilities. It's very easy to install, and it is 100% compatible with the standard OpenSim distribution.