The flights where the crew go above and beyond are always the best.

Nothing fancy for me, but in the early-mid 2010s I often found myself on the last NCL-LHR shuttle of the day on a Friday (in Y as a lowly Blue/Bronze). I usually came from work onto the metro straight to the airport. Sitting at the back of the mostly empty aircraft being plied with as many Tigers as possible with a crew who were clearly in the party spirit was just the antidote to a hectic, crappy week.