TripleA - TripleA is a free (under GPL) turn based strategy game based on Axis & Allies board game.
Realm of the Mad God - Realm of the Mad God is a best online hack and slash video game that includes pixel style graphics.
Domination - Domination is a game that is a bit like the well known board game of Risk.
Runescape - RuneScape is 3D Action-Adventure, Massively Multiplayer Online, Role-playing, Fantasy-based and browser-based video game developed and published by Jagex.
ThumbZilla - Awesome thumb stomping and kicking action game.
LaTale - LaTale draws heavily from some other 2D side scrolling video games to provide a great fantasy MMORPG world.