Whats the strangest thing you thought you saw and what did it turn out to actually be.
Years ago, we were stopped in the middle of the Indian River (Florida lagoon) when I spotted a small plane flying south, low and slow.
I commented to my wife: if that Japanese Zero starts to strafe us we'll have to jump overboard.
As it went overhead, we saw the red balls on the wings. It was going to an air show in south Florida.