This super-fast 3-D printer is powered by holograms
Ben Cummings

A bright-green laser flashes on, shining into a petri dish full of goo. From nowhere, the shape of a paper clip emerges-ghostly at first, then solid. Five seconds later the clip is fished out, cleaned up, and ready for use. The basic principle here is an established 3-D-printing technique that uses lasers to cure a light-activated monomer into solid plastic.