Danny Korem created a very elegant (and expensive) Zig Zag Card c. 1978. Then Mike Shelley and Morty Rudnick of Magical Mysteries released this version c. 1988 streamlining the method and it has been copied ever since.
It is simpler than Danny’s version, and is pretty much perfect. Very easy to do, with basic props made from thin artboard that don’t scream gimmicked, and there are no angle issues either. You you can sign the center of the card and watch the middle with the signature be slid all the way over right before your eyes!
I have a few other versions of this effect, but there is no question that this version created by Mike Shelley and Morty Rudnick of Magical Mysteries is the best I have seen. (Mike also created jumbo versions of this including one with Mickey Mouse, and he had Viking Mfg. create a collectors version made out of wood. In my opinion the simplicity of the original was also one of the reasons it was so effective.)
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