I just finished implementing the scoring for my first draft of the Tetris game for Interactive Digital Media, and that makes it complete enough to play.
You play by using the arrow keys. And presently you must reload the page to restart the game. I will polish it up a bit before it's due on Sunday.
Game was removed by request of the Tetris Company
If using Mozilla and the arrow keys do not seem to function, click the mouse in the content portion of the window where the game is located. That should make the keys work fine.