Eric Giler demos wireless electricity | Video on TED.com

Magnetic fields are ubiquitous. The earth has one that changes polarity every so often. And we all have radio waves going through our heads right now. But none of that is particularly caustic.

Is the cancer threat real? I know it's a pretty old technology at this point, but it's still not well understood.

Also, what kind of limits are there on transmission? Magnetism drops off at an exponential rate, so it's difficult to work with. I thought that was the issue tesla ran into.