Todays Science Lesson
Superconductor material, held below minus 181 degrees C, is repelled by a magnetic field. This phenominon is called the
Meissner effect of quantum levitation. The hover-cars are made of superconductive material, liquid nitrogen is used to cool the superconductor, and magnets in the track propel the superconductor along the track. The principle's been known for some time, and opens up exciting future technological possibilities.
See also
HERE