Mukesh Ambani

Reliance Industries

For a brief period in October, Mukesh Ambani was hailed as the richest man in the world. That's when his $23 billion group Reliance Industries, India's second-largest private-sector conglomerate, with interests in petrochemicals, oil and gas, and synthetic fiber, saw its market capitalization zoom to $63 billion. A chemical engineer, Ambani is credited with setting up the world's largest greenfield refinery in Gujarat. He has won many oil blocks around the world and is bidding for more. In 2005, Ambani had a very public split with younger brother Anil. In the division of the spoils, he had to let go of his cherished telecom business. Recently, he gave his wife a $59 million private jet as a birthday gift. Ambani is also building his dream house: a 27-floor mansion replete with two swimming pools, two underground car parks, a 100-seat home theater, and a helipad.