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Make that "every vibrating surface can be a potential microphone ..."

The laser on a hotel window experiment comes to mind.

Or an adapted Theremin

https://en.wikipedia.org/wiki/The_Thing_(listening_device)

with a high speed camera any vibrating reflective object like a potato chips bag can become a weak microphone if you have line of sight even behind a soundproof window: https://www.youtube.com/watch?v=FKXOucXB4a8

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