You may well have previously played The Ball. Toltec Studio's Unreal 3 mod generated a lot of attention back in 2008 during development, and then was released in 2009. It's sort of Weighted Companion Cube: The Movie. You move around the world in first person, but you interact by manipulating a large lead ball. It's used for puzzle solving, as well as crushing your foes. Now the project has become commercial, and is due to be released this Summer. Which means a new trailer has been created, and it's a goodun.
The final mod version is still available to download, and you can find it here. It's just over 500MB. The full commercial version is promising six hours of game, and a giant gorilla. Enjoy the trailer: