a new non-luminescent interactive display made up by stacking ping pong balls. each image is built out of 2700 tennistable balls in 6 greytones. the lowest line of ping pong balls will fall away so that the whole image moves 1 row down. by dispensing 45 new balls in the right order a new line is formed.
see also: displays with pixels represented as water droplets, air bubbles, water splashes, fire flames, LEDs & illuminated ping pong balls.