MSI has developed a new motherboard fan that uses the Sterling Engine Theory to power a fan without using any electricity.
This new fan uses waste heat from the CPU and heat is transferred from the motherboard northbridge chipset and through the Stirling Engine Theory it is able to spin the cooling fan and cool down the heatsink.
It is still in the early stages of development at the moment, here is a video showing how the technology works.
TweakTown via Gizmodo and Boing Boing Gadgets