Somewhat (maybe) related : another world from Éric Chahi used to support the pc speaker as sound output, and had digitized sound effects and voices (very low quality but still incredible).
This is: echo Magic Mushroom Echo -------------- echo This Program was made by the R&D Team at echo the Cleveland Corp. of Australia at Hendra echo To turn 'Magic Mushroom off press any key echo Bye,Bye,Bye
virus total scan (its clean): https://www.virustotal.com/en/file/34b703cace0a2464899c67fa1...
Because its so small (206K), it fits in a pastebin: curl http://pastebin.com/raw/D95mhEvE | base64 -D > mushroom.zip
[1] Actually only 6 bits per byte are used; presumably this was done to improve decoding speed or something.
curl http://pastebin.com/raw/uunJFtcK | base64 -D > mushroom.mp3
The result is 6 bits of resolution, along with a high pitched squeak during playback, depending on the output circuitry and speaker characteristics (it's less noticeable when a low-pass filter is added).