Never happened to me thankfully for all concerned. However, when at the Sheraton Towers Hong Kong my wife and I were walking down the corridor on the way to breakfast. The housekeeping trolley was in the corridor and a room door was wide open. As stepped around the trolley I glanced into the room and the guest was sitting at the desk stark naked, while the maid was working. An older guy, perhaps 60's or 70's. As we went down the corridor I asked Mrs F if she'd seen what I had and she confirmed that she had. Now bearing in mind that we were passing and I certainly didn't linger I was darned convinced that he wasn't wearing a stitch. What stunned me was both the fact that he seemed without a care in the world and that the maid was in there working. I know we could have been mistaken but I'm pretty sure we weren't.