By placing a magnet in a nerve-heavy location (such as the hand), you can gain a quite literal sixth sense – the ability to feel magnetic fields. Getting near a really big magnet – or even one of a moderate size, like those that hold a door/gate or that release magnetic security tags – can swiftly rotate the magnet within its pocket, which feels rather nauseating. Magnetic fields such as the ones provided by small implantable magnets are subject to the inverse cube law, meaning that the small amount of flesh surrounding them is enough to substantially weaken their operable field.