...completely blanked during a job interview?

I had an interview yesterday for an internal position. It was probably the third question they asked me and right after I started answering my mind completely went blank. I couldn't even remember what he asked me. I said, "I am so sorry but my mind just went blank. Can you come back to that question?" Luckily two of the other interviewers laughed and said they shouldn't schedule interviews at 3 PM because of the mid-afternoon slump and we moved on. I was able to bounce back with great answers the remainder of the interview but I still keep replaying that in my head.

Has anyone else had this happen? Or anything else embarrassing to make me feel better?