It uses Hall-effect feedback and lifts a neodymium magnet within a plastic
globe. The base also contains a rotating magnet which slowly spins the
levitated globe by weakly coupling to another NIB disk in the bottom of
the globe. I haven't disassembled mine yet, but the rotator looks more
interesting than the levitator. It has crossed coils with a pivoted
permanent magnet in the center. A polyphase AC motor driven by AC at
about 0.5Hz freq !
I haven't seen these for sale on the www. The box is covered with
"Discovery channel" logos, but the toy doesn't appear on their website.