Obsidian project is a OpenSource 3D network game for Linux and SGI.
Obsidian is an extensible virtual world system with a fullblown multiplayer client-server architecture. It is not a VRML2 world system, though there are plans to include VRML2 as a world data format.
Note that active development on this system stopped a while ago, though the code is still available for the curious. The code may not even compile on current Linux or Irix systems.
Here are some key features of "Obsidian":
· Multiplayer Client-Server architecture
· Generic TCP/IP hence works natively across the Internet
· Full 3D headsup with texture mapping
· Runs acceptably on a 486, screams on a Pentium
· Editable worlds and textures
· Supports some forms of IMPOSSIBLE ARCHITECTURE (eg. rooms that are bigger inside than out, corridors that curve back on themselves)
· Inter-player communications
· Projectile weapons (rudimentary, anybody is welcome to add more spectacular violence if they can)