Conducting a quick check ride with a junior pilot and did some autos with him. They were the first ones I did at 4500 feet above where I usually do them (sea level) and I didn't check the FM beforehand. Made for an interesting time at the bottom.
Someone older than me - a Wagners King Air pilot sitting on the ground waiting at Caloundra airport years ago - once told me - "never take the aircraft anywhere your brain hasn't already been". It's a good one.
Another time I kept referring to myself as a fixed wing aircraft when quizzed by Sydney ATC. I was in a helicopter. It had been a long few months and that was enough encouragement to go and have a day off.