A spectator threads a solid brass nut onto an ordinary shoelace-style cord. They hold tightly to both ends of the string so there’s no chance for the nut to escape.
 
You cover the nut with an ordinary cloth… and in an instant, the nut drops to the table!
When the cloth is whisked away, the cord is shown clean— the nut has completely vanished while the spectator was still holding both ends!
 
Easy to perform, impossible to explain, and compact enough to carry in your pocket for magic anytime, anywhere.