I flew back from Mexico City to Amsterdam a few months ago. Got chatting with a stewardess and she asked me what I did for a job. I told her I am an air traffic controller (which I am) and she immediately said "I'll go ask the captain if you can go have a chat with him on the flight deck." Cutting a long story short, I spent the rest of the flight (about six hours still to go) on the flight deck, including having my WBC breakfast being brought up to the cockpit for me. I used a spare headset and was still there for the landing. Very memorable flight for me, and also very useful for my job. Great crew and very friendly pilots. ^