I know we are all drawn to this place by our affection for words.
And discovering the origin of words is one thing I find quite fascinating.
But, there are many phrases we use that have obscure and even comically roots.
I was suprised (pleasantly) to learn the origin of the expression:
"Balls to the wall" It comes from the early days of air warfare, where the throttle controls for individual engines were levers - each with a ball on the top - and when they were pressed all the way forward; touching the firewall, the ship was at full throttle.
BALLS TO THE WALL.

Anyone have others?

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Did you ever wonder...?

"I am certain there is too much certainty in the world" -Michael Crichton