My secretary job usually doesn't have customer-service drama but today has a fun story. A student called in saying he had been hired by us in January but he wasn't working for us anymore so he needed his job removed from the system (BYU only allows students to have 3 on-campus jobs so I'm guessing he needed one removed to have a different one).
I ask for the student's name and I've never heard of him before. I do all student hiring so I knew this guy wasn't an employee of ours. I asked him which professor he worked for and, again, I didn't recognize the name. I said, "I'm sorry, you have the wrong department. That professor isn't in our department. Let me see what I can find out." The student then proceeded to tell me, aggressively, that I was wrong because he had come to my office, the Linguistics office, to be hired, so I must not know what I'm talking about.
I said, "Okay, hold please" and then proceeded to call student employment. I told them the situation (they laughed) and I asked if they could tell me where he's already hired on campus. Turns out he's hired for another humanities department. Sure, they do linguistic-y stuff, too, but we're on different floors. I tell the student this, he doesn't apologize (shocker), and I send him on his way.
Now, I've worked customer service at Universal Studios Hollywood. There is no customer in Utah who's gonna intimidate me. He didn't swear at me though so I didn't get to bust out my "Sir" voice. Oh, well. The best part of customer service, aside from helping people who were nice to me, was being able to put these people who thought they were SOOOO right in their place. Sweet customer service satisfaction.