Some things that have always been there but I've found interesting to note recently:
1. Woodwinds, harp and some percussion are the only instruments that don't have mutes.
Dudes. Flutes. Have no mutes.
Also funny is this.
2. Mutes have little to do with playing quietly.
3. Definition of percussion: instruments which are next to impossible to bring onto the stage quietly. Or by yourself.
4. Catgut has nothing to do with cats. It's actually the intestine linings of cows. Which is also what they used for old tennis strings.
5. In the past, there used to be a guy whose job was just to pump air so that pipe organs would function. Sort of like a human battery. Or like the guy who shovels coal into the boiler.