Tetris Unlimited is one of the many many versions of the game that have been made, and still it has lots of improvements.
The program comes with various game modes: Normal (1-4 players), Cooperative (2-4 players), and Competitive (2-4 players). For now the rest of the modes are yet to be programmed.
In addition, the board and the pieces are totally configurable. It includes enough options to create your own lever, with the ability to set your own piece order, time limits, etc.
In addition, the game's graphics are very well done and come with lots of sound effects.