In 1974, 3M scientist Art Fry came up with a clever invention. He thought if he could apply an adhesive (dreamed up by colleague Spencer Silver several years earlier) to the back of a piece of paper, he could create the perfect bookmark, one that kept place in his church hymnal. He called it the Post-It Note. Fry came up with the now iconic product (he talks to the Smithsonian about it here) during his "15 percent time," a program at 3M that allows employees to use a portion of their paid time to chase rainbows and hatch their own ideas. It might seem like a squishy employee benefit. But the time has actually produced many of the company's best-selling products and has set a precedent for some of the top technology companies of the day, like Google and Hewlett-Packard.