During the 1988 Christmas Season, my wife and I were shopping at Debenhams in Cambridge. We had our arms full of packages, waiting for the elevator on the second floor. When the elevator doors open, I started to step forward, but stopped short and almost fell as a gentleman in a wheelchair was exiting the elevator. Yup, I nearly fell on Steven Hawking. I was totally embarrassed and all I could muster was 'Sorry'.