Multris

Screenshots:

Background:
A Tetris style game, but with a multiplayer twist. You see your opponents play and if you clear more than one row at once you can send the other players unwanted rows that will be added from the bottom of the screen.

Features:
Pieces can be dropped straight to the floor, or dropped faster, or be dropped all the way down but without sticking to the floor, depending on what special keys are pressed.