I ask open-ended questions that aren't what people expect to hear. I hate interviewing someone who is obviously giving carefully rehearsed replies. Sometimes they are so determined to say "the right thing" they aren't even answering the question I asked. I tend to ask a number of follow-up questions to make sure I'm getting past the canned answers.
Example:
Q: Could you talk about a couple of the projects you have done working with a team?
A: We did a X and a Y at ABC company.
Q: Which project did you like better?
A: I liked X because the results were more successful.
Q: That's logical. Did the X project have a more talented team?
A: Well, I think the Y team was better actually.
So now I can ask
- What made X turn out better?
- How did the X team achieve better results with a worse team than Y?
- What kept the Y team from having good results?
Any of which will get past canned, prepared responses. I'm not as interested in the actual wording of the response as I am to see if the candidate can express a logical, thoughful opinion.
I also like to pause after a short answer to encourage the candidate to elaborate.
And I make a point to go over the negative aspects of the job as well as the positive ones. I want to make sure if people say they want the job, they are getting the job they expected. Example: "This position may require up to 25% travel and the work can be outside in all kinds of weather - cold, wet, hot, windy, whatever. You may not need to travel for a long time but if the need arises, you'll have to be able to go on short notice for a week at a time."
All I really want is for people to be honest in the interview. Don't pretend to be someone you're not because if you get hired, it's going to be obvious, and I'm going to be very unhappy. Be yourself so if you do get the job, the employer is getting the person they thought they interviewed.