This was my first success creating a homopolar motor.
https://www.instructables.com/Homopol...
I've always enjoyed playing with magnets, and these rare earth magnets are amazingly strong. So strong that they are slightly dangerous. They will attract each other from four inches away and snap together at disturbing speed. They are also difficult to separate once they have connected. It takes a lot of force to slide them apart, and they will reunite at the firs opportunity.
I found it quite difficult to get the wire on this balanced well enough to get it spinning and keep it going. I'm about to do some experiments to make it easier, like drilling a washer to keep the wire from eventually spinning off the positive contact. This version seems to clockwise. I'm trying to figure why, and whether that can be changed. I've already determined that putting the magnets on the other way up seems to stop it from working.