I've been listening to Glenn Gould's 1955 recording of J.S. Bach's Goldberg Variations quite a bit lately. As with most Gould recordings, if you listen closely you can hear him humming along while he plays. I find this infinitely interesting to listen to, but there are many who simply find it annoying. Anyway, I stumbled across this mock ad for "The Glenn Gould De-Vocalizer 2000" and laughed my ass off.