Not a question per se but when once interviewing a machinist candidate, the applicant was asked a question he didn't know the answer to so he paused, picked up the sample part being discussed, and (I kid you not), sniffed the part, put it down, shrugged his shoulders as if to say he didn't know and replied "I have no idea"! As expected, that was the end of the interview but not without a bit of a laugh. Almost as bad as another applicant who had to do a hands-on test at the mill and while at the control said (again, I kid you not) "I'm gonna own this b*tch!" (excuse the language) and actually DID! Some nice departures from the canned interviewing experiences.