Illusion stitches in Tunisian

Tuesday evening at Borders the group was talking about illusion knitting, and someone asked if you could do similar stitching in crochet. I remember reading an article in either Crochet! or Crochet Fantasy on this, I'll have to search for the magazine and take it in on Tuesday. I found it, it's Crochet Fantasy, Winter 2005.
In the meantime, he's a link to an "illusion scarf with alien heads"! It's done in Tunisian crochet.