Interactive bubble bouncer demonstrates MXP in real interactive multiuser environment. MXP is an open distributed virtual environment protocol with some novel ideas builtin. Detailed MXP specification can be found from: http://www.bubblecloud.org/
MXP is one candidate to become standard means of client to server communication and server to server interoperability. Typical applications would be systems like OpenSim, SecondLife, realXtend and their interoperation.
Interactive bubble bouncer demo client can be downloaded from: http://www.bubblecloud.org/
Client requires modern 3d video card (shared profile 2.0), Microsoft Windows with .NET Framework 3.5 and XNA runtime. If you do not have them you can download them install time.
If these requirements are too much you can check the video: http://www.youtube.com/watch?v=SiO7D_HDJR4