This picture was sent in by Russell Yee. He writes: " [The Exploratorium] was founded in 1969 by Dr. Frank Oppenheimer. As the Exploratorium was one of the first and is still among the very best hands-on science museums, one would expect some kind of entertainingly pedagogic feature to accompany these urinals: an explanation of kidney function, wastewater treatment, automatic flush sensor technology, urinal history--surely something, anything. Alas, there is nothing."