The Washington Post (June 22) -- In the late 1940s, Harvard researchers discovered they could cover up more than half of a speech recording without damaging a listener’s comprehension. The trick was to rapidly mute and unmute the audio. A team of engineers at Illinois soon had another idea: Instead of leaving the gaps in, why not cut them out and stitch the remaining slivers of audio together? For instance, deleting every other millisecond of audio would cause the recording to play in half the time.