I once saw my own kiai.
That is a great IRL story!
My IRL kiai story that made everybody laugh was the first time I was ever called upon to kiai.
It was while I was back east on a trip and visiting the late George Simcox Sensei at his dojo with some friends. He wanted us to do the ki test thing where you have people trying to hold you back and you walk forward...but he invited us to kiai as part of it...and invited us to just relax and vocalize/verbalise anything that came naturally.
Only one thing for a Brooklyn budobabe to holler as she walks forward, extending ki (and unbendable arm):