Richard Crowley wrote:
And even more bizzare, the really high-speed printers
(like the IBM "train" printer) hit the hammers so fast
that they would also produce quite loud musical notes
and people wrote code to play songs on them. The managers that ran the
computer rooms were generally
not amused.

Some of those printers were software-timed, which made this trick a bit
easier.

BTW, if you're interested in this sort of silliness, you really owe to
to yourself to dig into the early years of electronic music and musique
conrete. There some stuff that's unlistenable ("lab notes" from failed
experiments) but there's also some that's Good Stuff, and it'll teach
you a lot about how synthesis evolved to where it is now.