My wife used to work for a management consulting firm that welcomed new employees by having them stand up at the monthly company meeting and tell about their most embarrassing moment. She always came back with great stories. I figure there must be some here.
Mine happened when I was in college. I worked in a small video store. I'd been having terrible allergies which lead to a sinus infection which lead to gobs of dark green goo running down the back of my throat. I checked out a customer and looked around the store to confirm I was alone, then commenced some serious throat clearing followed by snorting, more throat clearing, spitting in the garbage can, etc, etc, etc... I was determined to hack up as much phlem as possible as the afternoon rush would start soon and I'd have to be more polite about it. I came up from dropping a major glob in the can to see a woman standing at the counter.
I wasn't nearly as alone as I thought. All I could say was, "Sorry... I've been sick."