It was 1996 or '97 & I went in to a restroom at a bar. A guy came in after me & proceeded to lay out a line of cocaine on the sink while I was pissing. I got done & he said "Hey, you want to do a line with me?" I was kind of taken aback. I was young, & had never really been around drugs harder than booze & the occasional joint at the time. I stammered something like "Oh, no thank you." & made a beeline to the door. I got back to my friends & before I could start to tell them what had just happened my friend Eric said "Oh my god! Did you see [very popular rock star at the time, but not really now]? He just walked in to the bathroom behind you!"

Edit: Took out the name of the person upon advice from other redditors