Backstory: I’m from central PA, not far from Three Mile Island. I was away at college the year the place nearly melted down.
One day I happened to walk in upon the future Papa Zappa (whose back was to me) and his roommates just as one of the roommates said “…mutant cows from Harrisburg”.
Without missing a beat, I said “Ooom?”, which was my beloved’s first clue that I was in the room. Everyone else went into hysterics while Papa Zappa / Typo Knig attempted to die of embarassment.
20+ years later, “ooom” still makes us giggle.