Caller: “Hi, I want to use my roommate’s computer but it’s not working.”

Me: “Could you describe the problem?”

Caller: “Well, there’s a sign next to it that says ‘In case of error, PEBCAK.’ Could you explain it?”

Me: *tries not to laugh* “It’s short for ‘Problem Exists Between Chair And Keyboard’.”

Caller: “Oh! I get it! Hold on…”

(I hear a loud cracking sound and some faint swearing.)

Caller: “It’s still not working!”

Me: “Er… what did you do?”

Caller: “I took away the wooden bit under the keyboard… now it’s right over the chair!”

(I actually head-desked after that.)