Tetris, written in Haskell & using GLUT 

 ★ Commands

 'q': quit, end Tetris.

 Left/right cursor keys: Move the current block left and right.

 Down cursor key: Move the block down the screen faster 
                  than it is currently falling.

 Space bar:  Rotate the block clockwise. 

 'z': Rotate the block counter-clockwise.