Resistors are very common. They slow down (resist) electricity. The colored bands code each resistor so you know how much electricity it allows through. If you find one in an old toy (and the legs are long enough) you can make a Resistor Brick.
Take apart some old junk and find a resistor. It is a small tan cylinder with colored stripes.
2 small binder clips
Find a resistor in some old junk.
Cut it out and try to keep the legs as long as possible.
Important: Sand each binder clip where it touches the resistor.
Add a binder clip to each side of you brick.
Insert the resistor legs under the clips.