A common question asked in an interview is, "What do you see as your greatest strengths?" and then the dreaded follow up, "What about your greatest weaknesses?" Nobody wants to answer that. If you go too far, you've lost the job opportunity and if you say something too shallow they can read right through it. One of the worst answers people give is, "Well, I'd say my weakness is perfectionism..." (They say this in a futile attempt of thinking the hiring manager is going to be attracted with that answer. They usually won't and can readily see through the insincerety that you are simply trying to build yourself up as someone who crosses every "t" and dots every 'i".) Some of us actually are that anal and perfectionistic, but it's not something you have to announce. If you are a perfectionist it will be readily noticed in everything from the way you communicated up to the interview point, to the way you are dressed. Besides that, only in the church is perfectionism viewed as a bad thing. Everywhere else it's practically revered.
So here's what this brilliant job seeker did. He knew this question was probably going to be asked so he prepared for it. When asked the question he said, "I thought you might ask that, and in preparation for that I called my former boss and asked them what they thought my greatest weakness was. Here's what they said..."
This communicated a few things to the interviewer...
1) This job seeker had guts! (To call their former boss and ask this question means they were not dealing with an insecure person.)
2) This person has a good enough rapport with their former boss to be able to call and ask the question.
The hiring manager was very impressed and the job seeker was hired.
Of course this will only work if:
1) You do have guts and are not so insecure that you can't ask this question.
2) You didn't burn your bridge with your former boss.