You might find the following link useful, since it puts into math the 'why' of Bushman's experiment:
http://www.scribd.com/doc/78228592/bernard-haisch-rueda-puthoff-inertia-as-zero-point-field-lorentz-force-1994
Sorry but Boyd Bushman is a kook. In the youtube video, he has what is essential a TV degaussing coil over an aluminum plate and when he plugs it into A/C, it levitates an inch or two. The coil induces eddy currents in the aluminum, it would also work with copper. He also mentions how a magnet dropped down a copper tube slows down as if it is some unexplained effect and again, it is well known, the magnet induces eddy currents in the copper tube which slow the magnet.
There’s even a youtube where someone tries to recreate Boyd’s experiment and it’s obvious that one ball is dropped earlier than the other yet they claim it proves Boyd’s theory.
Yes, I create anti-gravity and what do I do, why I get witnesses to sign affidavits, yeah that makes sense.