Keys

Keys predated locks.

The T-Rex awarded to the Triceratops the key to the city on account of his valor and bravery. The key didn't unlock anything. It was just a big dumb symbol for a big dumb lizard.

Human lock makers made clever use of the symbol.

Sometimes we still hand out useless, dinosaur-sized keys to useful people.

Your assignment for today: render a useless symbol tangible and fashion a very practical purpose for it.