MIT engineers have developed a technique to "listen" to sound without the use of a microphone—audio can be recovered just from video by analyzing how an inanimate object (such as a bag of chips or a plant's leaves) responds to sound vibrations. This means combining and filtering movements as small as 1/1000th of a pixel to retrospectively piece back conversations that took place near the object. By simply observing vibrations from a headphone cord connected to a computer, they were able to detect the song and recover the sound. The surprising discovery is that while the MIT engineers primarily used high-speed cameras, audio could also be recovered from video recorded on consumer-quality digital cameras. Spying just reached a whole new level.