The world's youngest billionaires

When Prince Albert von Thurn und Taxis turned 18, he inherited one of Europe's largest fortunes, including massive real estate holdings, a hefty stock portfolio and fine art. High school took the handsome prince to Rome, after which he headed to Scotland to dabble in economics and theology. The 23-year-old bachelor prince, worth $2 billion by our last estimates, also splits his time between his family's castle and touring with an Italian auto-racing league.

It is an enviable life, and an exceedingly rare one. Among the 793 billionaires Forbes found in 2006, only 11 of them, or one per cent, were under the age of 35. Of those, five inherited their fortunes, like Prince Albert. The other six created their own wealth.

The richest of this youthful crowd are Google founders Sergey Brin, 32, and Larry Page, 33, who launched the tech outfit in 1998 from a friend's garage. Since taking the company public in August 2004, the partners' meteoric rise in wealth has outpaced the rate set by the original boy billionaire--Microsoft Chairman Bill Gates.

Today, Brin and Page continue to help run the search juggernaut as president of technology and president of products, respectively. They are also two of the world's most eligible bachelors, although Page's days on that list may be numbered. He made the tabloids this year after reportedly escorting Lucy Southworth, a 26-year-old Stanford graduate student, to a number of Silicon Valley soirées.

Other relative youngsters who made their own fortunes include Anurag Dikshit, the Indian developmental engineer who wrote the betting software for online gambling outfit PartyGaming. He recently announced plans to step down from the board of the company to concentrate on product development and sold some of his shares.

Another pair of self-made billionaires are Russians Sergei Popov and Andrei Melnichenko, who teamed up in 2000 and proceeded to accumulate an industrial empire with interests in chemicals, steel mills, coal mines and banking. Melnichenko also made news last year when he hired Whitney Houston and Christina Aguilera to perform at his September 2005 wedding to a Serbian model.

All three of these tycoons--as well as Henrique Constantino, who controls Brazil's GOL airways with his three brothers, and Daniel Ziff, heir to Ziff-Davis publishing empire, who now helps run a family investment firm--are 34 years old, which means they will soon be too old for this "Under 35" list.

Only four billionaires are in their 20s, none of whom earned their money on their own. Three of the four are siblings: Ayman Hariri, 27; Fahd Hariri, 25; and Hind Hariri, 22, the two youngest sons and daughter of former Lebanese Prime Minister Rafik Hariri, who was killed in a car bombing.

Along with their two older brothers and mother, the Hariri children have been carrying on their father's heritage in business and politics. Ayman, for instance, fills the role of the family's tech geek, having started Epok, a privately held identity management software firm. His sister Hind, the world's youngest billionaire and the only woman on this "Under 35" list, campaigned for her brother Saad in Lebanon's recent parliamentary elections.

Slideshows:
Billionaire women we envy
The world's billionaires
World's most fabulous billionaire-owned hotels
Fortunes of kings, queens and dictators
Billionaire bachelors
Homes of the billionaires