In chemistry labs, it's quite common for solutions to be stirred with a little magnetic stir-bar with a rotating magnet under it.
Hang on, let's let a proper chemist explain:
Watching this, it seemed a bit complex to me... to start with electricity and then generate switching magnetic fields to rotate a spindle, then use that to rotate a magnet to turn a piece of magnetic material.
I wondered if it would be possible to turn a magnetic stir bar with the sort of rotating magnetic field used in some of the brushless DC motor projects I had been looking into.
This would be easier than a full-on BLDC project too... because they tend to require very high speeds and a magnetic stir bar is rather sedate compared to that.
I suppose this is what you could call an "induction stir plate".
So you'll be just putting the BLDC stator coils in the stir plate, and using the stir bar as the rotor? I like the idea! Keep us posted please!