Was flying to Le Bouget airport from an equally inconvenient airport in the UK with a colleague for a meeting in Paris.
She had forgotten her passport and decided to take a taxi back home to get it - a round trip of about an hour.
Fortunately she made it back in time. The check-in was casual then as there were very few flights from that airport and the plane had two props, with the "light refreshments" in a cooler box tucked under my seat when the life-jacket should have been. If you were a bit late for a flight, they just shoved the step ladder back up against the plane.
She was rather embarrassed about the passport incident and asked me not to tell anyone back at the office. I duly agreed.
She would have gotten away with it if she hadn't decided that, as the two-way taxi journey was very costly, she would include it on her expenses, which had to go to the boss for approval. No, he didn't.