A while ago I watched a documentary which at the end (don't let the name mislead you, I'm asking about a perfectly real phenomenon) shows an experiment which its inventor calls a "lifter"/ionocraft. The device, when a current is passed through it, hovers quite a distance above the ground.
He says that nobody at the time was sure exactly how it worked, though he did give examples of popular theories. But this was 2005, have there been any new developments in figuring out the science behind this device?
I am just fascinated by the device and want to better understand how it works and how it was constructed.