Minecraft. A game where you mine, then craft.
Obviously.
This game is still on the beta testing stage but millions of players have played it. What makes Minecraft so... addicting? It has no story at all and you just mine and craft things. The main focus of it is building while surviving. So why is Minecraft played by millions of users?
The graphics are blocky. In comparison to high-graphics games like Devil May Cry 4 (or the majority of Xbox360 games), it blows. But really, what's a building game without blocks? If its blocky graphics was changed to the graphics of a Xbox360 game, it wouldn't feel the same. It would probably feel like an over-exaggerated building game with elements of survival.
And then, the gameplay. It's extremely simple and straightforward with controls similar to a FPS's (a, s, d, w to move, space to jump, mouse click to interact) but it's different; you'll find yourself building and crafting all sorts of things. Perfect for the creative gamer with its redstone (it's kinda like electricity) and various other knick-knacks that pleases gamers looking for something creative to build with.
This is an awesome, addicting game that pleases the creative soul. 8/10.