Theoretical technology for relocating physical objects from one place to another instantly. The subject of science fiction TV and movies for decades we are still a long long way from being able to construct a working teleporter.
A commonly suggested though completely inpractical means with which to accomplish teleportation would be to store the complete atomic structure of the object to be teleported on a computer and then transmit that information to a destination computer where the object would be re-assembled. Given the enormous amounts of computer storage and energy required to perform such a task ( take in to account E=MC^2 when you consider converting a human being in to energy or vice versa ) this method is unlikely to ever work.
Other more exotic methods for achieveing teleportation include the use of wormholes or spacial warps to move an object from one point to another without travelling through the space in between, again a technology confined for now purely to the realm of science fiction.
Related entries: Teleporter Article Copyrightę Unexplained-Mysteries.com