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Researchers at Harvard are trying to create programmable matter -- meaning matter than can take any shape on command. At this very early stage of development, they've come up with a flat sheet of material that can fold into different forms:
Based on the ancient art of origami, the sheets are edged by foil actuators--thin, solid-state motors--that contract or expand when they receive an electric current from flexible electronic circuits embedded in the sheets. After they achieve their preprogrammed shape, the sheets are held in place by tiny magnets on the edges of the fold joints.
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