I've been a member of some interview panels and I can think of two interviewees that really stick out.
1. We were interviewing for an entry level position (this was at a county govt office before I got my engineering degree) that had really no room for advancement. We explained that we were looking for a long term person to handle daily tasks in our mail room/print shop. No matter what question we asked him, this guy kept saying that he was ready to be management, and he couldn't wait to become a manager, etc. I think he mentioned that at least 20 times.
2. We were interviewing an experienced engineer at one of the utilities I used to work at. We had an individual that looked FANTASTIC on paper. When she came in for an interview, you could tell she was extremely nervous. When she would get asked a question about certain experiences or instances to back up what she had done in the past, she totally locked up and by that I mean she literally could not get a single word out. I tried to help guide her or direct her to an answer by referencing some of the items on her resume, but even with that, she couldn't come up with anything. I've never seen an interview go any worse than that.
On the interviewee side, I was a year out of school and interviewing for a large machinery manufacturer. The position was to have oversight of the production facility and some design work on machinery components. The interview starts and after some brief intros, they pull out a picture of a large portable construction light tower. Then said, tell us how you would design this in detail, from scratch, show free body diagrams for major components, calculations for the hydraulics that lift the tower, etc. Needless to say, I tried to work through it off the top of my head, but knew I was unprepared and after about an hour of them throwing curveballs at me and pointing out how wrong I was, I figured I wasn't getting an offer (which I didn't care about after that experience).