The Next Generation of Billionaires

The most recent Forbes Celebrity 100 list estimated that 38-year-old entertainer Tyler Perry banked $125 million last year. The talented Perry, who produces, directs and acts in his creations, earned more than Jennifer Aniston, Tom Cruise and Bon Jovi combined. Building a billion-dollar fortune in the entertainment business is extraordinarily rare but certainly not impossible, as evidenced by Steven Spielberg, worth an estimated $3 billion, and George Lucas, worth an estimated $3.9 billion.

The diversity of this group shows you can't predict what industry the next billionaire will come from, but these people also have something in common. Even though they've accumulated more than enough money to retire in luxury, they aren't packing up for the Hamptons.

"I'm not really sure I believe in retirement," says Michael Birch. He worries he would be bored. He and Xochi are spending more time with their two children since the sale of Bebo, but they're also hunting for the next big consumer Internet hit.

Michael's returning his attention to BirthdayAlarm.com, a site the couple founded in 2001 but couldn't focus on because of Bebo and other ventures. "We're going back to give it some love," says Michael. The idea's simple--a birthday reminder site and e-card seller--but the potential's big. The site already has about 50 million registered members.

Elon Musk is also young, successful and full of big plans. He pocketed $22 million at 27 after selling the dot-com company Zip2. He followed that by co-founding PayPal. When the online payment processor was sold to eBay, Musk received nearly $170 million in eBay stock. The value of the stake only increased as eBay stock appreciated.

Now 37, Musk isn't splitting time between vacation homes but between a group of ambitious new businesses. His company, SpaceX, wants to provide cheap, reliable space travel to clients such as governments and satellite companies. Even though SpaceX is still working out the kinks in its launch vehicles, Musk says the company has been profitable for 18 months.