Only mildly related, but I have fond memories of my friend and I needing to wake each other up at different points in the 90's, and we had our neat-o Linux boxes next to our beds, and we would create loops that would echo ^G's to a tty on the console.

But if you sent them too fast the sound would completely cease, so we would have to put a sleep 1 in the loop to make a nice consistent beep-beep-beep-beep, etc.

That always amused us, and sure was useful.