Fortune 500 rank: 372
David Murdock got his start in business at age 22. He was a high school dropout, broke, and homeless. He even occasionally slept under a bush in a park in Detroit. Still, Murdock managed to cobble together the cash to buy and fix up a diner, which he sold at a profit. Then he drove west and got into real estate.
Flash forward 40 years, and Murdock's housing business generated enough profit to fund a string of increasingly large acquisitions. He bought a controlling stake in a mining company, a gas company, and -- in 1985 -- Dole Food Company, a subsidiary of a struggling Hawaiian firm. Murdock shaped Dole into a $6.8 billion business -- and the world's largest producer of fruits and vegetables.
These days, Murdock says he feels great. He eats an incredibly strict diet of mostly plants -- including citrus rinds and banana peels.
Fortune 500 rank: 307
O. Bruton Smith's path on the fast-track to racing fame was unlikely: he grew up in a poor farming family, never went to college, and got his start in the business while also working as a car salesman.
Today, Smith's Speedway Motorsports operates eight racetracks and hosts major NASCAR events. Smith is famous for pioneering the luxury, lighted tracks that helped fuel the sport's wild popularity. He also has his hand in a variety of other industries and is the head of Sonic Automotive, which operates more than 100 car dealerships.
Smith's business success is likely thanks to his penchant for driving an incredibly hard bargain. Reports from his early days at the Charlotte Motor Speedway have it that when he had a pay dispute with workers, he showed up to the construction site with a posse and a shotgun. (The work got done.) Since then, he's been known for bringing a similar -- if less violent -- passion to boardroom negotiations.
Fortune 500 rank: 5
For decades, Warren Buffett has been the patron saint of aspiring businessmen the world over. Not only is he known as the greatest investor of all time, but he also has a reputation as charitable, honest, and possessed of a keen, if folksy, wisdom. A typical Buffett sound bite: "You should invest in a business that even a fool can run, because someday a fool will."
Preaching a gospel of value investing, charitable giving and sound corporate governance, Buffett has been a hugely influential force on the world of business over the decades. His company, Berkshire Hathaway, has also climbed into the ranks of the Fortune 500 and Fortune's list of World's Most Admired Companies. The company raked in $1.6 billion last year, and despite a bout with testicular cancer, Buffett has indicated he has no inclination to retire.
Fortune 500 rank: 91
Hacking scandals. A flailing newspaper industry. An attempted pie to the face. Rupert Murdoch's recent travails would make even the boldest consider retirement. But it's hard to picture Murdoch sitting beachside.
The Australian media mogul is the owner of News Corp., an entity most famous in the U.S. for producing the conservative network Fox News. Murdoch's other holdings include Twentieth Century Fox and the National Geographic Channel. He also controls about 175 newspapers, including the Wall Street Journal and the New York Post, which will be spun off into a separate company mid-2013.
That publishing business has caused trouble for Murdoch recently. The public's appetite for print has waned in recent years, and hacking scandals at the News Corp.-owned tabloid The News of the World shook Murdoch's entire media empire. Once details of widespread phone tapping emerged, the tabloid was promptly shuttered, but the revelations landed Murdoch and his associates in court. At one hearing, an overzealous protestor came at Murdoch with a pie, only to be spectacularly thwarted by Wendy Deng, his quick-reflexed wife.
Las Vegas Sands
Fortune 500 rank: 244
Sheldon Adelson has a knack for choosing his bets wisely. The IPO of his casino company Las Vegas Sands in 2004 made him a very rich man. Today, Adelson now controls one of the world's largest personal fortunes, and he hasn't been shy about spending it.
According to The New York Times, in 2012 Adelson became the biggest single donor in political history, when he gave more than $60 million to a handful of Republican candidates and causes. Mitt Romney may not have won the presidency, but that wasn't because Adelson didn't do his part.
Las Vegas Sands operates casinos, hotels, malls, and resorts in Asia and the U.S. It has a particularly spectacular portfolio in Macau, the largest gaming market in the world and the only Chinese territory where it's legal to gamble in a casino. In Macau, it operates the Sands Macao, the Four Seasons Macao, and the grandiose Venetian Macao, which has 460 table games and 2,200 slot machines, plus a 39-floor luxury hotel tower. The company has, however, run into trouble in the region, and it recently acknowledged that it likely violated some provisions set by the Foreign Corrupt Practices Act.
Roger S. Penske
Penske Automotive Group
Fortune 500 rank: 203
When Roger Penske retired in 1962, his career revved up. At that point, the 29-year-old was a successful race car driver. That year, he hung up his helmet, started his own racing team, and opened a Chevrolet dealership in Philadelphia.
Today, Penske runs the Penske Automotive Group, which operates 344 dealerships, along with a vast array of other transportation businesses, including auto rentals. He also entered the racing record books with his team, Penske Racing. The team won 15 career victories in the Indy 500, more than any other team in the history of the sport. His nickname is, simply, "Captain."