Wiggles

Two photos of a subject, taken a few inches apart, shown in quick succession as an animated GIF, result in the illusion of depth and motion.

Also see the Mars Rover Wiggle series.

The author's one true love in 3D. View from the Art School at Old Church, Demarest, NJ Sleeping cat My nose

See the original wiggle GIFs here:
Jim Gasperini's Stereo Images - Time for Space
3D Images of Burning Man 2002