Tell us about yourself!
Tooth pastes not only clean, but also leave a protective layer against tooth decay thanks to the fluoride that they have, so stop making your own tooth pastes at home.
It surely should look nice when spinning. What I don't like is that there's no on off switch, instead of putting one, next version you could add something to switch on the lights only when the thing is spinning, just like those yoyo toys you may know.
I actually thought two things, and almost forgot the second one. Why not using a little dc generator instead of the ballbearing? since we only need only about 30 ma, maybe the little generator will be able to generate and put out what it's needed when it's rotating at enough rpm, is not it great?