Danish researchers work on the fridge on the future based on magnetic cooling. The technology is based on the fact that energy is released if magnets are exposed to an external magnetic field and that's as far as I understand the physics part of this story

It is a promising way to cool, because it is environmental friendly and power efficient. Environmental friendly, because instead of heavy and toxic fluids, the cooling fluid can be just water. Power efficient because the only necessary energy is needed to move the magnetic field. The fridge should also be more quiet than todays versions. A workable prototype is expected in 2011, rapid use in consumer electronics is not likely. The consumer industry must adapt many processes first. Associated
researchers foresee that industrial use will come first, especially in low-noise environments.