[Not single-page] Sara Blakely went from auditioning to play Goofy at Disney World to founding an undergarment empire: Spanx. She still owns 100% equity in the company, making her the youngest female billionaire at age 41:

Like many startups, Spanx began life as an answer to an irritating problem. The panty hose Blakely was forced to wear at both Disney and Danka were uncomfortable and old-fashioned. “It’s Florida, it’s hot, I was carrying fax machines,” she says. She hated the way the seamed foot stuck out of an open-toe sandal or kitten heel. But she noticed that the control-top eliminated panty lines and made her tiny body look even firmer. She’d bought a new pair of cream slacks for $78 at Arden B and was keen to wear them to a party. “I cut the feet off my pantyhose and wore them underneath,” she says. “But they rolled up my legs all night. I remember thinking, ‘I’ve got to figure out how to make this.’ I’d never worked in fashion or retail. I just needed an undergarment that didn’t exist.”

“Undercover Billionaire: Sara Blakely Joins The Rich List Thanks To Spanx.” — Clare O’Connor, Forbes

See also: “The Billionaire King of Techtopia.” — Jonathan Miles, Details, Aug. 23, 2011