Firestorm Viewer is an LGPL client used for the group user-constructed simulation environment called OpenSim. There is a Linux version but it has major issues with audio and can be unusable. There is a Mac version but I have no experience with it. It's based on the Linden Labs client, which is LGPL, so by the terms of the LGPL the Firestorm Viewer must also be LGPL.
OpenSim is an Open Source online virtual environment with user-modifiable avatars and such.
For more details and user comments, view the versions of this application
|Latest Wine version tested
|Latest version of the viewer as of August 10, 2022.