Well, I have been thinking about this recently quite a bit as almost exactly 2 years ago I got OFF a flight due to a "feeling". Here's what happened:

I had flown my first flight to PIT and had about a 3 hour layover for my flight to LHR. I was going to be gone for a week on a buying trip for my business. My DH was in a pressure situation with his job (which is in sports). Ugly season = NASTY/UGLY people.

Anyway, I boarded the plane for LHR with my carryon. I was in the middle section of 4 seats and was thinking "Wow, there are only 2 of us in this row, yeah". Had my book out and was even belted in. Out of the complete blue I got the feeling that I needed to turn around and get back home. Since I was carryon and the door was still open, I was able to gt off.

To this day I do not know if the feeling came to me due to DH's situation or just that inner voice protecting me from something in the future. Never had the feeling it had anything to do with the plane.

Someone recommended the movie "Sliding Doors" to me after this. It was a good recommendation. I've never changed my travel plans before this or since.