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 v

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.