William Wrigley, Jr., the founder of Wrigley Gum, ran away from home at the age of 11 to escape working in the family's soap manufacturing business. He went to New York, where he sold newspapers, but soon was back home. In 1891 he left for good, going to Chicago to make his fortune.
In the beginning Wrigley continued to sell soap, offering a free can of baking powder as an incentive to his buyers. Soap sales weren't strong, but people loved the baking powder, so he started selling it exclusively while now offering two pieces of gum as an incentive. He soon discovered that the gum was even more popular than the baking powder, so Wrigley went into the gum business.
Similarly, the name Levi Strauss is synonymous with blue jeans in American culture, but the man by the name wasn't thinking about jeans when he went to California in hopes of making his fortune during the gold strike of the 1840s and 1850s. He did make a fortune, but not the way he had planned.
He set out with a load of heavy canvas fabric, from which he planned to sell sections for tents and wagon covers. Upon arrival, the first miner who saw his product said, "You should have brought pants." The seasoned miner further explained how there weren't any pants strong enough to endure the tough condition of mining. Levi Strauss immediately made the miner a pair of work pants, and thus struck gold.*