About 15 years ago magnets were all the rage. I had a friend who's uncle was part of a pyramid scheme to sell magnetic insoles and other items. He came out to give us a demo of his products. He had a massager with magnets in it, and a little gizmo that lighted up when you introduced EMF to it. He spun the massager to show us how the magnets created an electric field and caused his tester to light up.
I was an electronics student at the time and understood magnetics and electricity. I grabbed my electric mixer, plugged it in, and ran it next to it's tester. The tester, of course, glowed much brighter with my mixer. I then asked him why I should buy his massager when I could accomplish the same thing by using anything that had an electric motor.
I don't think he liked me much after that.