Catznip Second Life Viewer - Catznip is graphical client for Linden Lab's user created 3D virtual world, Second Life.
OpenTTD - An open-source clone of the classic game ...
Firestorm Viewer - Firestorm is to Virtual Worlds what Firefox and Google Chrome is to the Internet. We develop and distribute an open source viewer for accessing Virtual Worlds.
Simutrans - Simutrans is an open-source transport simulator.
Second Life Viewer - Download Second Life from the official site here.
Transport Tycoon Deluxe - Transport Tycoon Deluxe is a Business Simulation developed by Chris Sawyer and published by MicroProse.