Take a look at this video of Daniel Rozin's Wooden Mirror, which uses hundreds of small wooden squares (appropriately lit) as pixels.
(Daniel Rozin's Wooden Mirror video)
A camera captures the desired image and the digital picture is translated by the device, which in turn moves each wooden square to capture enough light to properly illuminate that "pixel".
In their 1990 novel The Difference Engine, William Gibson and Bruce Sterling describe a similar device, the kinotrope:
A mechanical frieze, a slow sort of kinotrope for Aaron's adverts, made all of little bits of painted wood, clicking about each in turn, behind leaded sheets of bevel-glass.
The pixels are spun by steam powered crank machinery which is driven by a difference engine. The Difference Engine reads a stack of punch cards in automated succession to map which pixels to spin at which time. As the cards are run through it, the pixels spin along in time.