Soap seller William Wrigley Jr. switched to hawking baking powder in the late 19th century. To drum up business, he gave away chewing gum, and eventually he realized that customers were more excited about the freebie. The gum stuck.

The payoff: Now a Mars subsidiary, Wrigley is the world’s largest gum manufacturer.

Fusajiro Yamauchi founded Nintendo in 1889 as a purveyor of playing cards. His great-grandson unsuccessfully expanded the company into taxis and “love hotels” before hitting gold in the early 1970s with an electronic shooting game.

The payoff: Gaming domination via Super Mario Bros., Game Boy, Wii, Pokémon Go, etc.

The mouthwash was first marketed as a general-purpose antiseptic, meant to get rid of both household grime and, um, gonorrhea. In 1914, pharmaceutical company Warner-Lambert started selling it as a halitosis remedy.

The payoff: Current owner Johnson & Johnson sold $340 million worth of the stuff in 2015.

The Minnesota Mining and Manufacturing Company (get it? 3M) originally planned to sell excavated minerals to manufacturers. But when that didn’t work out as planned, it shifted to producing finished items, such as sandpaper.