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It is well known that you cannot float a stationary permanent magnet in a magnetic field established by other permanent magnets. This was proved by Ehrenfest (see www.ccmr.cornell.edu/~muchomas/8.04/Lecs/lec_TDSE/node8.html). However, you can float a magnet over a superconductive disk (this apparatus is sold by Edmund Scientific, though you are on your own to get the liquid nitrogen required), and you can float a diamagnetic substance over sufficiently powerful magnets at room temperature.

It is this last effect that is demonstrated here. I was able to get the slip of pyrolytic carbon to float a bit higher than what is typical by thinning it down to a fraction of a millimeter.

The carbon and the extremely strong magnets are available from my friend Simon Field (www.scitoys.com), whose site has a good explanation of what is going on.