Bling-y Blings!
So you're stuck in class on a beautiful sunny day, and your teacher is droning on and on about mid-century modern architecture when you notice a particularly well-placed beam of light reflecting off your jewelry. And if you turn it JUST SO, you can aim that beam of light right in her eyeball. Repeatedly. Until she throws a little hissy and runs out of the room. Now wasn't that worth the cost?