Sound in a Jar

If someone says something into an object, like a jar, and then close it, the sound will be preserved and released upon opening or the object’s destruction.

Literature

 * Soul Music has sound-capture boxes,

Live-Action TV

 * In the Daily Show John Stewart does swears into a veterans affairs swear jar, in a later episode, original airdate 5/19/2014 he opens the jar and (censored) profanity comes out.

Western Animation

 * In SpongeBob, this happens in Naughty Nautical Neighbors, with bubbles
 * In The Amazing World of Gumball Darwin is underwater and speaks, bubbles come out, pop on the surface, releasing his words for gumball (and us) to hear.

Real Life

 * The field of Archaeoacoustics opened up the possibility of a variation on this idea, that under some circumstances it might be possible for pottery thrown on a wheel to accidentally encode, in the manner of an old Edison cylinder or vinyl LP, nearby sounds. Around the middle of the '00s, the idea caught the public imagination and started showing up everywhere.  Sadly, the Myth Busters showed that only the most general of acoustic phenomena could get so encoded.