Winding a toroid for Tesla's egg?

Tesla's original exhibit for the 1893 Chicago World's Fair used 2 phase power on 4 coils wound on a toroid in a bucking configuration like so:

http://www.youtube.com/watch?v=Ec4u4BfS4tE&lr=1

The bucking configuration causes the magnetic flux to leave the metal core and fill the airgap, similar to a deflection yoke in a CRT, which in turn causes the egg to spin in a way similar to the rotor in an induction motor.

My question is this: with modern know-how, how would you create such a device (say using 3 phase power), and more to the point, how best to efficiently generate a main field inside the airgap (or better, slightly above it) of a coil and minimize stray field?

All practical (use a the stator from a three-phase motor or 3 pairs of Helmholtz coils with 3 phase power) and crackpot (use Rodin and starship coils) ideas are appreciated.