Opensim
Get flash to fully experience Pearltrees
OpenSimulator is an open source multi-platform, multi-user 3D application server. It can be used to create a virtual environment (or world) which can be accessed through a variety of clients, on multiple protocols. OpenSimulator allows virtual world developers to customize their worlds using the technologies they feel work best - we've designed the framework to be easily extensible. OpenSimulator is written in C# , running both on Windows over the .NET Framework and on Unix-like machines over the Mono framework.
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