Still pictures that move
Pinna–Brelstaff illusion
Look at the dot and move your head toward the picture and back. What do the rings do?
They turn, the two rings opposite ways. Nothing in the picture moves.
Why? As you come closer, every square spreads out from the dot. Each part of your eye sees only a slanted edge, which seems to move sideways along the ring, and the edges in the two rings slant opposite ways.
Picture: Drawn by Science Playground