Caption: The coffee at the end of the rainbow. The end of the rainbow seems to be entering the coffee sitting on the gunwale of a boat.

But if the observer moves, the rainbow moves and you never drink from the Fountain.

Credit/Permission: National Oceanic and Atmospheric Administration (NOAA), Image ID: corp2028, NOAA Corps Collection; Photographer: Commander John Bortniak, NOAA Corps. Photo Date: 1992 September / Public domain.
Image link: Itself.
Local file: local link: rainbow_coffee.html.
File: Electromagnetic Radiation file: rainbow_coffee.html.