Physicists in Japan have made a device that can detect individual electrons that are flowing either forwards or backwards. The device — the most sensitive ammeter to date — allows currents to be measured in the attoampere range for the first time. Dubbed a bi-directional single-electron ammeter, the device could be used for a wide variety of applications, including nanoelectronics, calibration devices, quantum computation and biology (Science 312 1634).

“The single-electron counter should be useful for detecting extremely small current in various applications,” say Fujisawa and colleagues. “It should be especially useful for studies on nanoelectronics (which seek to examine electron transport through nanostructures), single molecules, and biological cells.”
(Source: PhysicsWeb)

Wow. The implications for nanotech are enormous. I’m also intrigued by the mention of investigating biological processes with this kind of accuracy.

Really, there’s not much else I can add apart from another wow.