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Another fun example of braking are the electrodynamic tethers [1], in which you (a satellite) are the copper tube and the entire earth is the magnet!

[1] http://en.wikipedia.org/wiki/Electrodynamic_tether

But it's possible to the same experiment with a battery and an electro-magnet, isn't it? (Not sure how the power-density of lithium-ion batteries would relate to floating 80 kgs down a tube... but seeing as people have demonstrated hover-boards, it should be doable) ? Assuming the purpose is a) float down tube, and b) SCIENCE! -- and not c) with rare earth magnets...

Yea my hs physics teacher demoed this and talked to us about possible applications for a while. i don't remember any but thank you wikipedia: http://en.wikipedia.org/wiki/Eddy_current#Applications