One of the theoretical particals in physics that has yet to be discovered is a Magnetic Monopole. This a particle that has either a North or South pole, but not the other end. OK, someone has just given you unobtanium, and it is a unusual magnet indeed. It has a North pole, radiating in all directions. What what you use it for? If we could make an electromagnet version that could be aimed in a specific direction the uses would be immediately obvious, a tractor beam comes to mind for example. A magnetic field with the directionality of a laser, that could be turned on and off. I've never read anywhere where they defined what a monopole field would look like.