A team of computer scientists at Carnegie Mellon University has developed a technology that makes run-of-the-mill paper move on its own.
The paper is cut into a shape, such as a flower, and treated with a thin conductor that's either applied by a 3-D printer or painted on. It adds only a half millimeter of thickness. The paper is then folded or bent into a shape and heated in an oven.
At that point, an electrical current, heat, or touch will cause the paper to uncurl; when the stimulus is removed, the paper goes back to its natural curled state.