Today while traversing the corridors of the University, I came across this sign:



It's a promotional sign for the nanotechnology lab of the University of Twente, apparently they're diving into the energy harvesting material science. Although probably not relevant to what they're actually doing, the demo is funny; you can light up each LED corresponding to the peltier tile:



No fancy processing needed here: behind each peltier, a small converter modul harvests the energy and powers the corresponding LED: