(YouTube link)
"Relativity" is an art project by Drzach & Suchy in which pictures are created using raised tabs. The art is revealed by the shadows of the tabs, and the picture changes depending on the direction of the light. This particular piece is called "Marilyn". Link -Thanks, Drzach & Suchy!
http://www.youtube.com/watch?v=RlUg-aHFKBg
it really is an incredible thing to see animated pinscreens
Pinscreen animation makes use of a screen filled with movable pins, which can be moved in or out by pressing an object onto the screen. The screen is lit from the side so that the pins cast shadows. The technique has been used to create animated films with a range of textural effects difficult to achieve with traditional cel animation.
The technique was developed by Alexandre Alexeïeff and his wife Claire Parker, they made a total of 6 very short films with it, over a period of fifty years.