Sadly, you can't beat the physics with today's magnets. Magnetic monopoles are still sci-fi, so the strength of a magnetic field over distance falls of with an

Sadly, you can't beat the physics with today's magnets. Magnetic monopoles are still sci-fi, so the strength of a magnetic field over distance falls of with an inverse cube law; the field strength is proportional to 1 / (distance ^ 3). For the same reason, electromagnets need to use an enormous amount of power to be effective over long distances. That's why people get these magnets implanted; because they sit right against the nerve, and the distance is on the order of nanometers. Hurts like heck to get it in, though.