I was browsing throught the Jim Henson Book at Borders a few years back and came across a picture that had an early version of CM before he was a regular on SS. He was in an old IBM commercial eating a machine of some sorts. He was pretty scary looking, as he had sharpteeth and looked to be a darker blue color. In the early SS episodes he was never really referred to as 'Cookie Monster', from what I recall anyway. He would just show up eating anything in sight.
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