This one is, perhaps, ten seconds into the future, but I think we just about have the technology for it.
The surface of each piece of the jigsaw is actually ePaper, or some similar addressible medium, and hides a wifi or Bluetooth receiver and circuitry, that keep the piece's picture updated real-time.
completed jigsaw shows a clock of some kind - Big Ben, a brightly colored alarm clock, maybe just big block letters - the actual design is settable from the central unit that keeps the individual pieces' pictures updated.
Coming next, or maybe even in the same box: the moving picture jigsaw (with special extra-difficult option - the bouncing ball on a white background).-- DrCurry,
Mar 10 2008random,