Art Fry
Post-It Notes
In 1968, Fry's co-worker at 3M invented a not-very-sticky glue that nobody knew what to do with. A few years later, Fry was in church, frustrated that the little pieces of paper he stuck in his hymnal as bookmarks kept falling out and he realized that a not-very-sticky glue could be used to make small pieces of paper temporarily stay in place.

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