A flight I was on last year, I can't remember where to, I was in 2A and I noticed the passenger in 1E stripping off to change at his seat. Top half was changed first, then came the bottom half. Unfortunately Mr 1E wasn't wearing any underwear so I was treated to the sight of a half covered naked posterior for a few seconds until the bottom half was in place, at the same time as he was trying to pull the top half down as far as possible to protect his dignity. Amused me no end. To be fair it was his first F as I had overheard the jist of his conversation with the CSD during their welcome greeting. I'm glad to say he got re-dressed in the toilet at the end of the flight.