Flying Around a Möbius Strip
This is too cool — and quite literally cool at that! The following video from the Royal Institution is a fantastic demonstration of the wonders of superconductors. Here we have a superconductor “car” zipping around a magnetic track shaped like a möbius strip. And yes, that does mean it’s moving upside down for half the track.
The real action starts at about 4:50, but you should watch the whole thing as it gives a great explanation.
Phil Plait also has a good explanation on his blog as well.