MySims Kingdom - MySims Kingdom is based upon The Sims series but provides special and extremely different gameplay to the original series making it definitely worth your consideration.
The Universim - The Universim is an Action, RTS, Open-world, Sci-Fi, City-building and Single-player Simulation developed and published by Crytivo Games.
Gaia Online - Gaia Online is 3D Social Networking, Virtual World, and Browser-based Simulation.
Populous - Populous is an Action, Role-playing, Real-time Strategy, Single and Multiplayer god game developed by Bullfrog and published by Electronic Arts.
YoWorld (Yoville) - YoWorld or formerly known as Yoville, is an Action, Browser-based, MMO, RPG, Single-player and Multiplayer, Social networking, and Virtual World Simulation developed by Big Viking Games.
Spore Hero - Spore Hero is a Single and Multiplayer Life-Simulation developed by EA Montreal and published by Electronic Arts.