Paper Thin sound (thermoacoustic effect)

Nanotubes have extraordinary strength and unique electrical properties. They are efficient conductors of heat and are the width of a strand of hair.
Chinese scientists found that very thin carbon nanotube films, once fed by sound frequency electric currents, could emit loud sounds. The scientists demonstrated in YouTube videos that their prototype could blast a scratchy but understandable version of the Moldovan pop song "Dragostea din tei" while it was taped to the side of a waving flag