Interesting aside to a discussion about the Leica M8:

As an aside on the whole sensor size issue—I guess there is some practical or economic limitation that keeps most sensors at 75% of the standard 135 film size, thus forcing all of the rethinking of lenses and such, but it’s interesting to note where the 35mm standard came from. Apparently, in 1889, Thomas Edison was developing the Kinetoscope and a worker asked him how wide to cut the film. He held up his thumb and forefinger and said “About this wide…” and the 35 millimeter standard was born…