Prince Alwaleed bin Talal

SPHERE OF INFLUENCE: This nephew of Saudi king Abdullah is the world’s 19th-richest person—and the wealthiest of all Arabs. He built much of his $21 billion fortune with a stunningly shrewd investment in Citibank when it was struggling in the early 90s. Now the devout Muslim is Citi’s biggest individual shareholder—and the largest foreign investor in America, with stakes in News Corp. and Time Warner. Charming, candid, and progressive in his outlook—he hires women for key positions—he’s highly mobile and well connected: this spring he toured 23 nations, meeting with Bill Gates, Warren Buffett, and Rupert Murdoch.

BIG LOSS: Alwaleed, 53, lost billions when Citibank’s stock price collapsed because of the subprime-mortgage crisis—and he joined with other big investors to infuse $12.5 billion in new capital into the troubled bank. But his losses were partly mitigated by gains from his holdings in the Four Seasons and Fairmont hotel chains, which have thrived in the Middle Eastern market.

WINGS: Boeing 747-400 while he waits for delivery of his $310 million Airbus A380 Flying Palace. It’s expected that the superjumbo jet will have a gym, formal dining rooms, and a cinema. It’s so big that it can land only at airports in major cities.

CRIB: 317-room palace in Riyadh. It features four separate kitchens for four different cuisines: Lebanese, Arabian, Continental, and Asian.

EVIDENCE OF POSSIBLY EXCESSIVE BEHAVIOR: Travels with a staff of 60.

LATEST ACT OF DO-GOODERY: Donated $15.7 million apiece to Cambridge University and the University of Edinburgh to build new Islamic-studies centers.