Can you help
Invent the Adult toy - Universe in a bottle.

With an electro magnet at the center as well as a - electrode the particles, if slightly magnetic would tend to orbit nicely as the entire globe would turn.

Does anyone know which light metals are slightly magnetic?
Calcium, titanium, Sodium etc?

Also the specific gravity of the (empty) medium and particles should be as close as possible to each other so they would distribute nicely and not just sink or float. If there was also a material that would represent gas that would be irridesent or glow in an electric field the effect could be super. I know that Sodium will glow brightly when stimulated with microwave. They use that process to imitate sunlight with 99% accuracy.

Kids be the first on your block to turn on The Universe in a bottle.

Art
this could be way cool.