MIT's piezoelectric fibers can act as speaker or microphone, don't mind auto-tune

Piezoelectric materials work quite simply, in theory -- motion in, electricity out, or vice versa -- and since that's just how speakers and microphones transmit their sound, it's not much of a stretch to imagine someone would figure out audio on a micron scale.
That someone is MIT's Yoel Fink, who's reportedly engineered a marvelous process for producing fibers that can detect and emit sound. Following up their famous work on flexible cameras, Fink's team discovered they could keep piezoelectric strands rigid enough to produce audible vibrations by inserting graphite, AKA pencil lead. Better yet, the lab process can apparently make the threads on a fairly large scale, "yielding tens of metres of piezoelectric fibre" at a single draw. The potential for fabric made from such fibers is fantastic, of course -- especially combined with this particular scientist's previous research into camera cloth.