One of the most impressive bits of science I have seen in a while, really very cool, though I am a little unsure of the applications. The video is a must watch. Which by the way is distributed as bittorrent file, one of those evil P2P technologies that various industry groups want to kill.
We present a novel photographic technique called dual photography, which exploits Helmholtz reciprocity to interchange the lights and cameras in a scene. With a video projector providing structured illumination, reciprocity permits us to generate pictures from the viewpoint of the projector, even though no camera was present at that location. The technique is completely image-based, requiring no knowledge of scene geometry or surface properties, and by its nature automatically includes all transport paths, including shadows, interreflections and caustics.Link
(Via MAKE: Blog.)