Random Screen is a mechanical thermo dynamic display which does not rely on any electricity.

Each of the 12 by 12 cm pixels is built as a seperate module. A tee candle lights and controls each pixel. The rising heat of the candle turns a modified beer can which turns the pixel on and off. Each pixel has its own frequence. The more bright a candle shines the faster is the rotaion of the can.

Video.
Also by Aram Bartholl: Bits on Location and Punchcards pixels.