I answer the phone at my work, politely as usual.
"Hello. This is Eric Anderson at Sterling. I need to speak to whoever is in charge of ordering your printer supplies."
I say, "I'm in charge of..."
"Noooooo, you're not. Your boooss is. What's his name?"
"It's JJ, but I AM the one who orders the..."
"No, I'll call JJ back." Click.
Note how he automatically assumed my boss was a "he." What a prick.