Ah.

A very unkempt middle-aged man with a crazed look in his eyes walks up to the info desk.
Man: "Do you have a book?"
{Now, because he looks serious, intense and not well, I forgo sarcasm and ask:}
Carrie: "Yes. Which book is that?"
Man: (now twirling the hair at his right temple in his finger and staring just off to the left) "Jeffrey Dahmer."
Ah.
Well, as it turns out, the books on Jeffrey Dahmer were all out. I, well, frankly, reluctantly, directed him to the true crime section, as he giggled maniacally and continuing to twirl his hair. Ooh, the downtown branches.

Next up, a middle-aged guy walks up to my desk looking very annoyed and entitled.
Guy: What's the problem?
{That's it, that's all. Like I'm supposed to know what the *#!&*(& he's talking about!}
Carrie: (laughing, somewhat hysterically, as a way NOT to snap his head off) I don't even know what you're talking about.
Guy: (in a tone that implies I'm supposed to know already) The computers! They're not working!
Ah.
But of course. Silly me for not being an IT mind reader. I feel completely enlightened by your well communicated, fully thought-out, direct and detailed question and answer. Come again!

This reminds me of the laziest NON-question I have ever had, back in the day, when I worked at the Blackburn Hamlet branch. There was a regular patron, a middle aged woman who did a program with learning disabled adults who would come in every week and expect the diva treatment, meaning no effort on her part, full effort on ours. Normally, she would walk up to the desk, tell us a subject and ask us to collect all the books in the library with good pictures of this topic. This one day, she didn't come up with even that much.
Woman: Do you a book, with, uh, a, little bit of, uh, everything?
{Insert internal explosion here}
Carrie: (in a steely, "are you sure you want to ask that?" tone) You want a book with a little bit of everything?
Woman: (taking a step back and looking less certain, but still going for it) Uh, yes?
Carrie: (in a similarly-themed "believe me, after this, our conversation is done for today" tone) The generalities are in the 00's, behind you.
Woman decides to go and look herself.
Ah.
I am not usually so un-professional, but I swear the thing that drives me the most crazy the fastest is people who expect you to both provide the question AND answer it, without them having to trouble themselves with any action of any kind. Press button A... I have found since, though, now that she has set the gold standard in this kind of behaviour, I find every other version of the question does not annoy me to the same degree. So, in a strange way, I do thank her for blowing out that circuit so I don't have to do it twice. Zen and the art of library work.