OpenTTD - An open-source clone of the classic game ...
Monster Galaxy: The Zodiac Islands - Monster Galaxy: The Zodiac Islands is enticing new Adventure, Puzzle and RPG video game by the popular Gaia Interactive Inc.
Simutrans - Simutrans is an open-source transport simulator.
Zenforms: Protectors - Zenforms: Protectors takes you to a whole new world of challenging Puzzles, amazing Adventures and RPG elements and allows you to immerse yourself into a very immersive and quite engaging game-play ever.
Transport Tycoon Deluxe - Transport Tycoon Deluxe is a Business Simulation developed by Chris Sawyer and published by MicroProse.
Pocket Frogs - Pocket Frogs is an Addictive, Hunter, Breeding, Training, and Single-player Simulation developed and published by NimbleBit LLC.