Oh my goodness! Do my eyes deceive me, or have bobby pins not yet been recognized for their incredible utility?
Apart from the obvious use of keeping your hair up or out of your eyes (which they’re really good at), some of the helpful uses I’ve found include:
As an emergency stylus, either as is or straightened out. As a pointy thing to push a recessed button, such as a hard reset button. As a lockpicking tool. (I’ve only picked things like bedroom door locks, but I have read–no doubt in scholarly journals–that they can also be used for more serious lockpicking tasks too.) As a paperclip, bookmark, or other weak clip to hold something like a bag closed. As a replacement for a broken zipper pull. To fashion a very crude hook or pokey stick thing for any number of purposes, from getting something out of a drain to deflating a ball.
A bobby pin is just a small metal stick with two rubber ends, which can easily be removed with your teeth if you need a metal end or a finer point, which makes it unusually versatile. The best part is that they’re dirt cheap and super portable. You can just carry them around in your hair!