Question: i know that magnets can be used to create small (toy sized) hovering vehicles however in your opinion do you think this a technique that could be used on a mass human sized scale?

Fiona Coomer answered on 21 Jun 2013:

There are two ways that a magnet can be used to make a vehicle hover. One way is to use the fact that a magnetic field repels a superconductor. If you can cool a superconductor below its superconducting transition, you can create a levitating train. At the moment, even the ‘high-temperature’ superconductors need to be cooled by liquid nitrogen to actually superconduct – it wouldn’t be possible to do this on a large enough scale to transport humans, so at the moment it remains a pretty cool lab experiment.

The other way, is just using the fact that the north poles of two permanent (or electro-) magnets will repel each other. A few maglev trains have been made this way – the first one was at Birmingham Airport, but it has now been replaced: http://en.wikipedia.org/wiki/AirRail_Link.