A team of researchers at the Technische Universitaet Muenchen (or TUM) led by Dr. Willi Auwaerter and Professor Johannes Barth appear to have made something of a breakthrough on the road to the miniaturization of everything. They've devised a molecular switch that measures just one square nanometer, but is able to switch between four distinct states on demand. That was done by placing two protons inside a single porphyrin ring; when one of the protons is removed, the other can then move to any one of the four available positions with the aid of a small current. According to the researchers, that process not only allows for the smallest switch implemented to date, but one whose state to be changed up to 500 times per second. The official press release is after the break.