Louie Zong asked people to send him clips of themselves singing a note. He got over 200 of them, freaked out, and eventually turned them into a musical keyboard to make songs with. Here's the first one. https://www.youtube.com/watch?v=SpmYHPQdIs0
Reminds me of Ze Frank's "Chillout" from 2010, made from audio recordings over 30 people sent him, all singing the same chorus independently. The Flash page he made for it is long-dead, but he tells the story in this TED talk here. https://www.youtube.com/watch?v=3gSSNHO1dDs#t=14m21s