Traditional logic represents "1" and "0" by rather sharp voltage levels – something that noise makes difficult to control in nanoscale circuitry. William Ditto of Arizona State University in Tempe and colleagues have built reliable logic circuits that rely on noise to work.
The idea is to exploit stochastic resonance, whereby noise can boost the detectability of an otherwise low "1" signal, while not driving a "0" signal to look like a "1". The nonlinear circuitry used for the logic gates offers another advantage: suitable control voltages used rapidly to make a single gate act as a NAND or a NOR – enough for any other logic circuit.