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.
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.
Tinierme - Tinierme is a Massively Multiplayer Role-playing, Fantasy, Virtual World, and Browser-based Life-Simulation.
Wandering Willows - Wandering Willows provides a universe full of missions and wildlife where gamers will attract pets, teach them, and more.
Gaia Online - Gaia Online is 3D Social Networking, Virtual World, and Browser-based Simulation.
Virtual Villagers - Virtual Villagers collection is a selection of life simulation games.