Basically the voltage even from a turned off TV is enough to generate movement.  For the experiment all you need as a list of the following:

• One sheet of aluminum foil..can be any brand generic from the supermarket

• Plastic pen

• A tab off of a soda can

• One piece of thread

• Two coke cans or any aluminum soda cans

• Any type of wires although lligator clip wires work the best

• Old school TV set not plasma or lcd