OpenSimulator
= the open source implementation of Second Life Metaverse
URL = http://opensimulator.org/wiki/Main_Page
Description
"OpenSim is the open source implementation of Second Life (but using .NET, alas); its existence is what makes the new Open Grid possible. Without the open source behind it, this would simply be a closed approach similar to old-style online services such as AOL or CompuServe. Linden Lab's decision to open up its protocols means that there is a chance to create a virtual world equivalent of the Internet, which anyone can use, and where anyone can contribute." (http://www.computerworlduk.com/toolbox/open-source/blogs/index.cfm?entryid=1095&blogid=14)
Technical Details
"OpenSim was created with libsecondlife, an open source library derived from the source code to the Second Life's viewer. The code that operates SL's server grid remains closed source, however, so OpenSim is a fully open alternative.
As leading OpenSim developer Adam Frisby stated:
"We used the term 're-engineered'-- it was re-implemented from standards, but on the backend it's a very, very different beast. As best as we can tell (without seeing the source to the Linden Lab server), the structure internally is radically different partly due to our desire to keep things usable for non-SL style worlds."
OpenSim is the leading platform for 3D websites in a way that Apache is the leading platform for 2D websites.
Over two dozen on the OpenSim group's Grid List ( http://opensimulator.org/wiki/Grid_List) have emerged with many designed to serve specific groups and activities, such as for the Chinese market. Reactiongrid, an OpenSim area, is now running on SQL Server, Microsoft’s offering in the highly-competitive database market.
There are many veiwers for OpenSim including realXtend, The Hippo OpenSim viewer, - The Opensim Kid Browser and Xenki." (http://thefutureofartificialintelligence.blogspot.com/2008/09/ai-93-apache-platform-for-2d-websites.html)