An old fashioned, walnut wooden frame is handed out for inspection along with a steel blade. The blade is slid into the top of the frame and a wooden match is placed into the smaller of the two holes. The spectator is invited to place his/her finger through the larger of the two holes.
The performer thrusts the blade downward, "through the spectator's finger," but breaking the wooden match. The spectator's finger is unharmed!
Everything can be examined before and immediately after the effect!