My uncle, on my father's side, once took me to the home of an inventor friend of his. This was in 1962. The man lived on Belvedere Street, here in San Francisco. My uncle told me this man had invented the Touch Tone phone. I don't know how I knew about the Touch Tone phone, because it wasn't rolled out publicly until 1962. The Touch Tone phone is technically a dual-tone multi-frequency, as I learned later when I worked with Capt'n Crunch the king of the 1970s phone phreaks.
What struck me as bizarre is that this great inventor was fanatic about his “greatest invention,” the electric cigarette that would some day be mounted on top of taxi cabs. When the cigarette was lit up, with a red light where the burning end was, the taxi was available. When the cigarette wasn't lit the taxi was occupied. The photo on the left shows a current taxi with an illuminated message sign on top. (Cigarettes on the top of taxis never made it.)
Somehow I knew, back on Belvedere Street, that I would rather have royalties from the Touch Tone than from a potential cigarrette sign on a cab.