My wife always put an 'H' on the hardboiled eggs with a pencil to make sure they aren't confused with the raw. When my daughter was in elementary school, they were one of her favorite snacks. So when I'd make them, instead of the 'H' I'd draw a little something. I'm not any great artist, but I'd draw a butterfly or a cat or some silly face. I didn't realize for ages that they apparently became a sensation at school and the other kids always wanted to see the day's egg.