This is just outright incredible. Using the grooves in pottery found at Pompeii, arcaeologists have been able to record sound from Pompeii including identifiable laughter. The page is in French, as is the clip, but you'll know the recording from the waveforms and the sound (unless you speak French, that is.)
http://www.zalea.org/article.php3?id_article=496
Click on "Lire la video"