Big Ideas, Big Bucks

29 years of backbreaking work and long hours, Marsha's company, United Scrap Metal, is one of the largest scrap metal companies in the country. The Illinois-based business is bringing in a revenue of more than $140 million, and Marsha employs almost 200 people.

When Marsha first started out, she says men would surround her truck and yell obscenities as she loaded car batteries and iron pipes. Their taunts backfired. Marsha says the obstacles she faced only made her stronger.

"I was underestimated," she says. "I was the first woman ever to do this. ... The more they underestimated [me], the harder I worked."

"[You're a] great inspiration to women everywhere," Oprah says.