"Branson is 54, so it's not likely that he'll be around for the next hurricane that hits Necker's 74 acres of beaches, lagoons, palm trees, volcanic rock outcroppings, and Balinese-style pavilions. And he's running out of the dangerous sporting escapades that enthrall him. He gave up trying to fly around the earth in a balloon after an American, Steve Fossett, did it first. (Branson had to be rescued from the sea five times by helicopters.) Now he's financing a venture to send tourists into space. He plans to go up on the first Virgin space voyage, but thinks that will be several years away.

Until then, Sir Richard will have to rely on business for the danger he craves. There aren't many challenges left here either. Branson has been superrich for a long time -- his net worth is more than $2 billion -- and he has indulged his entrepreneurial instinct by starting an astonishing number of ventures: His Virgin Group comprises 350 companies he founded; they took in $8.1 billion in revenues last year. Earlier this year, Virgin had $450 million in cash ready to invest.

If they're right, the thrill-seeking Branson may finally be diving into one adventure too many. He has led a charmed life so far -- a man with a Midas touch who seems to be able to turn every whim, hobby, and surmise into gold. But beneath the showmanship, the seeming effortlessness, and the Boy Billionaire lifestyle, Branson is a tenacious, focused, and creative entrepreneur who has defied the naysayers time and again. The experts thought he was insane 20 years ago, for example, when he started out with only one airplane to launch Virgin Atlantic. "He's charming and disarming," says one of his executives, "but he has a razor-sharp mind behind that.

So again, why start all those companies? "I love learning about things I know little about," Branson says. "I love people, and I don't like to say no all the time. We've got people all over the world who are coming up with great new ideas, and it doesn't actually cost us a lot relative to the overall size of the group. Four months ago, I went into a juice bar in Sydney called Pulp. Fantastic. Healthy. Delightful staff. I knew the guy who set it up. So let's give it a go outside Australia."