ASCII Bell Character
The other day, I accidentally printed a ton of binary data to my terminal. Upon doing so, my computer started to beep incessantly - which startled me a bit. I looked through the list of processes, closing all the terminals, but the beeps persisted.
Turns out this is a feature, and not me going insane. The ASCII value 7 is the Bell character, one of several control codes or non-printed characters in ASCII. Apparently this dates back to the days of teletypewriters, where it was used to ring a physical bell (as opposed to just a digital sound).
This article points out that it can even happen in the case of the Unicode bullet.
It just so happened that my data was full of 0x07, and all the beeps queued up, running the entire time as I searched Google and Wikipedia for solutions. The answer in my this case was to use the command net stop beep, found on this Stack Overflow post.