[SectioAurea]

See also the Coral Castle legends in more recent times.

Would be extremely interesting if this worked on a macro scale. They are floating nuts and bolts with a small desktop device.

I'm also curious about power draw/requirements.

Apparently they are using arrays of Langevin type sandwich transducers to generate the ultrasound, of the type used for industrial cleaning applications (example http://www.ipfonline.com/products/index/langevin_type_sandwi...).

What happens if you have an array 2x2 meters? Or 20x20? Does the wave have to completely encompass the object to act on it, without exception? In that case we may need to revisit the lower frequencies and attempt to move balloons, etc. Some relation to the resonant frequency of the object being targeted may be involved.