Back in the "Good Old Days", pre 2001, I had a few visits to the flight deck, but the best one was in 1984, flying back from Naples on a British Airtours Tristar...the co pilot showed me the instruments, and I remarked what Mach number is that? and he looked at me sideways and said "what do you do?" "Air Traffic in the RAF"..says I..He showed me the chart, explaining where we were and what arrival into Gatwick..at this point the Captain, who had been silently doing the crossword, turned around and pushed down the little folding jump seat, and got me a head set..I stayed all the way into Gatwick, only leaving when we got to the gate...Such a treat!
A very belated thanks, guys!