This lead in appears on Slashdot yesterday, I guess I can sneak this in as an energy topic, they have a wild discussion, as usual, going on about it if you go to the Slashdot site:
"Although a staple of Sci-Fi space travel, it is often deemed to be just that: Fiction. However, it seems that one is currently in development. "The theoretical engine works by creating an intense magnetic field that, according to ideas first developed by the late scientist Burkhard Heim in the 1950s, would produce a gravitational field and result in thrust for a spacecraft. Also, if a large enough magnetic field was created, the craft would slip into a different dimension, where the speed of light is faster, allowing incredible speeds to be reached. Switching off the magnetic field would result in the engine reappearing in our current dimension."