This very informative (and beautiful)) video from the Royal Institution (starring Andy Mermery) has a cool demo on the repulsive force experienced by a magnet when it is moving near a conductor (or a conductor moving near a magnet). Since force can be made stronger if the resistance in the conductor is brought down, Andy takes a piece of high-Tc superconductor (yttrium barium copper oxide) and lets it glide (and be guided) on a track made with powerful neodymium-based magnets on both sides of a Möbius strip. Andy also explains the piece stays “locked” to the track irrespective of whether it is above or below the track; the currents set up in the piece due to its relative motion with the magnet produce forces that oppose that motion.
T.A. Abinandanan 