Engineers at Binghamton University in New York have developed a folded paper battery that generates power by leveraging the process of microbial respiration, in nothing more than a drop of dirty water on paper. The system uses liquid-containing bacteria that are used to power a paper-based sensor.
The battery folds down into the size of a matchbox. Actual origami techniques were used to create the three-dimensional structures, which can be stacked top one another.
This folded paper battery is a marvelous feat of engineering. Its unique workings make it particularly useful in situations and places with little or no access to electricity. It could potentially be used to create diagnostic tools in the developing world, seeing as how the bacteria-based power source can be easily sourced from wastewater and biomass.