With a generous interpretation, they can be said to break classical thermodynamics, since they quantum physics onto the table, most notably magnets can have negative temperature according to the statistical definition. Nothing that breaks physics at large, but would probably cause Ludwig Boltzmann a mild headache if he heard about it.
It's still not going to allow you to make perpetual motion machines, though.
It's still not going to allow you to make perpetual motion machines, though.