Effect: Performer takes a spool of thread, unravels about a foot of it, & then breaks it off, putting the spool down. Performer proceeds to break the thread into 6 or 7 clearly broken & different pieces, then holding one piece in one hand, the other pieces are rolled up into a ball and 'squashed' onto the piece from the other hand. When this is unravelled it is seen to be completely restored to it's original length. VERY visual, & very clean, pretty easy to do as well. Here's the routine.