I had a lady pull up beside me and tell me I had a brake light out. Pulled over and had my co-pilot hit the brakes, no problem. My only thought was that she only saw the one light and didn't realize the other fender has NO brake light or it was the most deadpan joke delivery I've ever heard.
Reminds me of a story I heard Jay Leno tell. He was out in his Morgan 3-wheeler and a guy pulled up and said he lost a wheel. He laughed and went home.... turns out his spare fell off the back