Two guys I know through the local hackspace have had this done.
One is a cable/internet tech, and claims that it may have saved his life - you can't perceive voltage potential, but you can "sense" current flow.
He was standing in a puddle of water, and was reaching towards the inside of a cable box on a house, and "felt" current flowing through it. Investigated, and found that the line into the box had been rubbing against a household electrical wire, and had worn through the insulation on both, causing a short that was carrying power through the box.
That's for sure. I wonder how safe these sort of implants are even when just playing around with other rare earth magnets. Having the implant ripped out because you absentmindedly picked up another magnet would really suck.
I know literally nothing about this, but would posit the hope that if multiple people have cared enough to implant an object under their skin, at least one of them would have considered a less-permanent solution like a ring before hand and tried it out.
One is a cable/internet tech, and claims that it may have saved his life - you can't perceive voltage potential, but you can "sense" current flow.
He was standing in a puddle of water, and was reaching towards the inside of a cable box on a house, and "felt" current flowing through it. Investigated, and found that the line into the box had been rubbing against a household electrical wire, and had worn through the insulation on both, causing a short that was carrying power through the box.