You might already know this, but it's news to me. Arthur C. Clarke went to a Bell Labs demonstration in 1962 or 1963 featuring an IBM 704 singing the song "Daisy" (or, more properly, "Daisy Bell") and it made a huge impression. This was also the first real-life example of a singing computer.

Strange Horizons editor Jed Hartman has more details, and then adds:

Speaking of which: in response to the query "sing me a song," Siri will recite the beginning of the chorus of "Daisy"-but won't actually sing it. So fifty years on, we still don't have singing computers in daily life. Another failure of living in the future, like jetpacks and aircars. I'll have to console myself by listening to the Dictionaraoke version of "Video Killed the Radio Star" again.