Good interview questions include "Tell me about a project or accomplishment that you consider to be the most significant in your career" and "Tell me about a time when things didn't go the way you wanted." A less common yet telling question is "What's your animal power?"
Another great open-ended question is "Tell me about a recent project or problem that you made better, faster, smarter, more efficient or less expensive." If the candidate has held several jobs in recent years, the best way to understand work history is to ask, "Why have you had X amount of jobs in Y years?" The interviewer should close the interview by asking, "What questions do you have for me?"