As a child I was very serious about memorizing the "red touches yellow" poem for telling the difference between coral snakes and milk snakes, and to be frank, I'm kind of disappointed it hasn't even once come in handy.
Knowledge is like that. But you never know, life's not over yet. I memorized lists of things I'm never going to use in life, like the names of all the cranial nerves, the dynasties of China, the gravity of planets, etc. All useless trivia now.