And the calculations are not easily done on the back of a napkin.

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"I'd like to buy the world a Coke and keep it company, " Backer wrote on the back of a napkin.

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And that number--published by the New York tabloids--is little more than an educated guess made on the back of a napkin.

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But house prices went up by more than double that amount, and about 65% in the seven years from 2000 to 2007 (back-of-the-napkin estimate).

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Let that project or new idea that you have been drawing on the back of a napkin come to life.

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Japan's system, having been devised on the back of a cocktail napkin in a Ginza bar by Douglas MacArthur in 1945, is different.

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Instead, Barcelona, who had been made aware of his talents, offered to pay the medical bills of a boy who stood just 4ft 6in as long as he was prepared to move to Spain, a decision which Messi confirmed when signing his first contract with the club on the back of a paper napkin.

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The engineers at Flextronics call them napkin products because they usually start out on the back of one.

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She went back in without the wig on and pieces of napkin still stuck to her head.

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