They always ask you about your best/worst trait; about the biggest success/worst failure of your career; why you left your previous job; what you liked most/least about your previous job; where you plan to be in 1/2/5/10 year(s). Start thinking about the answers to that stuff, and write down your responses; that way, when they ask you those questions, you'll be relaxed when you answer 'em.
Eek...I don't think I *have* any "big successes". I've never headed up any big projects. I've always been just a team member...a bitty cog in the great workings of whatever-my-department-was-called. I'd like to think I'm a very good and dependable bitty cog, but I guess that's not likely what they're thinking about. And the few projects I have headed up haven't been anything important...something like just inventorying a companies computer assets for the first time isn't very impressive when the company is only 50 people or so.
I shall ponder, I guess. And writing stuff down is a good idea. It's the best way to sort out thoughts, IMO.
I'm kinda screwball in my interview questions. My favorite questions are:
-- What did you do for the most fun on a weekend?
-- What is the best fun trip you ever had?
-- Tell me about the first computer you ever used.
-- Tell me about your computer at home. Did you build it, or buy it? Why?
By the end of that discussion, I pretty much know what I need to know about that person.
IMHO.