Tetris ... passatempo per gli amici di internet ...:-))

• cursor key left
  falling block goes left
• cursor key right
  falling block goes right
• cursor key up
  falling block mirrors
• cursor key down
  falling block rotates one quarter
• space bar
  falling block falls down with light speed
• P
  pause/continue
• R
  restart

Known limitations (i.e. bugs):

• The vertical bar (three blocks on top of each other) cannot rotate
  
• No checks if there is room for block if it is mirrored just before it is landed
  
• Game over and wissetris images do not appear the first time