Strong magnet is very useful. That is why there is a geopolitical tug of war going on between China and other countries over rare earth minerals used to make very strong magnet. China is the largest miner and processor of rare earths and has threatened to cut off export of these materials to other countries that make products with them.
The torque of a permanent magnet motor is a function of the strength of the magnetic fields in it. You can either increase the strength of the magnets, increase the current in the windings, or both. To make a motor of a given size have the most torque with the least use of electricity you build it with the strongest possible magnets. Other devices like hard drive voice coil mechanisms (which position the heads on the platter) also benefit from stronger magnets so they can move faster with less power consumption.
Basically almost anything that uses a magnetic field from a permanent magnet to do work, generate electricity, or steer beams of particles (MRI machines, nuclear physics particle accelerators, etc.) can benefit from the strongest possible magnetic field from the smallest possible magnets. Hybrid and electric cars simply would not be even close to practical without rare earth magnets becuse the motors would be too big and use too much energy.
Strong magnets are in your Hard Drive, the optics steering hardware of every CD and DVD player in the world, your hybrid or electric car, and hundreds of other applications.
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