[asteram]

Looks good to me, khephran. That's the concept as I envision it. What I would add to the idea:

The frame needs to be an easily available non-magnetic material; plastic, even wood; if metal, aluminum would be a good choice.

The pyramid would need to be held in position from its bottom point as well. An aluminum rod epoxy-glued to the tip would do that. It needs to be free to rotate. The simplest way to do that would be to put a point on the ends of its supporting rods and have the points resting in a little cone-shaped cup that could be oiled or greased.

The pyramid should also have a means of adjusting it up or down, closer to or further away from the balls. That's a little trickier to do unless the pyramid was drilled through its length and had a set-screw tapped into it to lock it in place on the rod, or a ring and set-screw glued to the base. Another idea would be to have the rods supporting the pyramid going through ball bearings, with a locking collar at each end that could be loosened and moved, once again to be able to adjust it up and down.

I'm also wondering about the N-S magnetic fields of the pyramid; assuming N is down on the pyramid, and N is up on the balls, would it just float or would it try to spin? What effect would steeper sides have? Could the pyramid be made so that the sides alternated N-S-N-S? Would that do anything?

Understand that I'm just thinking out loud here. Hopefully one of the other readers is actually trying this out.