Actually, I disarmed a hostile call back in my tech support days. My accent is very "New Yorker" apparently, and I got a call from the Deep South.
After a few questions from me to diagnose the problem, feeling some hostility, he finally came out with a shouted demand, "ARE YEW AH YANKEE???"
I blinked a few seconds, and answered quite honestly, "No sir, I most certainly am not!"
"Yew ahll right then" was his reply, and we got the job done.