A couple of years ago AOL published this article listing the top five questions that would throw any interviewee for a loop. Thankfully they include answers that would reflect well on the respondent.
Aside from being difficult, they are excellent questions to help you inventory your background, achievements, strengths and weaknesses. If you have an interview coming up, it certainly wouldn’t hurt to look them over and see how they might apply to you.
You never know, even if no one asks them, they will get you lighter on your mental feet for whatever your interviewer has in mind.