A couple years ago a friend of mine mentioned that he had known another mutual friend of ours for many years, much longer than I would have guessed. I asked him "what does he do?" and he thought for a moment before saying "you know ... I have no idea, it has never come up".
I don't know if this is acceptable in the US, but I always found it distasteful when people ask about your job 30 seconds into meeting you. I think it's much more polite to talk about generic stuff until jobs or skills come up naturally. Sometimes, they just never do, and that's fine. Need to know!
Definitely one of his more interesting qualities.