Well, FO's really are co-captains. One of the most irritating questions I get every once in a while is "And do you actually, like, fly the plane? I thought you were there just to push buttons". And the ever-so-popular "I thought you just helped the captain."
And this ones really ticks me off "You have to study to be a pilot? All you do is press buttons, besides I read in (insert newspaper, magazine, etc) that airplanes land themselves everywhere and anytime."
Sigh.. it happens.
But the most outrageous question I have ever heard (was asked to a friend, not to myself):
Person: "So, you are studying to become a pilot?"
Friend: "Yes"
Person: "A pilot?"
Friend: "Yes"
Person: "Hmm, I have always wondered, where do copilots go to school?"
.. Three Green