This has been all over the internet recently. It's a famous hack (read: prank) pulled at MIT where you can play tetris in the windows of the tallest building in Cambridge. There is a control pad to the left of where I'm taking this picture and what you see in a snapshot of a live game of tetris that 18 stories tall. A few offices left their lights on on the upper right side, making the playing board a bit distracting.
