Dan Gilbert is chairman and founder of Quicken Loans. He is also majority owner of the Cleveland Cavaliers and operator of Quicken Loans Arena. In addition, he recently led the purchase of the Lake Erie Monsters (of the American Hockey League).

Quicken Loans, the nation’s largest online home lender, closed nearly $19 billion in home loans in 2007. FORTUNE ranked Quicken Loans #2 in its 2008 survey of the “100 Best Companies to Work For,” the fifth consecutive year the company placed in the magazine’s top 20.

Since becoming majority owner of the Cavaliers in March 2005, Gilbert has overhauled the franchise, including $27 million of upgrades to Quicken Loans Arena and the $25 million construction of the team’s state-of-the-art training center. In 2006-07, Gilbert’s second full season of ownership, the Cavaliers advanced to the NBA Finals for the first time.

Gilbert and his partners operate and invest in several consumer-based, technology-centered businesses, including ePrize, an online promotions company; Fathead, the maker of life-sized wall graphics; Veritix, which has created paperless tickets for sports and entertainment events; and Xenith, which has developed helmet technology that reduces the risk and severity of concussions and other traumatic brain injuries.

Gilbert, who earned his bachelor’s degree from Michigan State and his law degree from Wayne State, recently launched Bizdom U, an entrepreneurial academy that trains, mentors, finances and helps launch young entrepreneurs and their start-up businesses in Detroit.