"If you've ever wondered what a virus sounds like, or what noise a bacterium makes when it moves between hosts, you may soon get your chance to find out. Scientists have created the world's tiniest ear. The 'nano-ear,' a microscopic particle of gold trapped by a laser beam, can detect sound a million times fainter than the threshold for human hearing. Researchers suggest the work could open up a whole new field of 'acoustic microscopy,' in which organisms are studied using the sound they emit."