Jigsaw puzzle manufacturers often use the same die-cut pattern for many different puzzles. This makes the pieces interchangeable. As a result, I sometimes find that I can combine portions from two or more puzzles from the same publisher, to make a surreal picture that the publisher never imagined. I take great pleasure in “discovering” such bizarre images lying latent, sometimes for decades, within the cardboard boxes of ordinary mass-produced puzzles.
Via kottke.org.