Roman Abramovich, 41, Millhouse Capital
This erstwhile oilman may be the oligarch most Americans know best, not for his fortune but for how he spends it. Abramovich, worth an estimated $24 billion, reportedly was the buyer who broke records at the New York City art auctions in May with his purchase of Francis Bacon's "Triptych, 1976" and Lucian Freud's "Benefits Supervisor Sleeping" for a combined $120 million. Add to that his celebrity-filled parties (Amy Winehouse sang at one), his private jet, a yacht rumored to be outfitted with two helicopter pads and anti-paparazzi lights, and - oh, right - the world-famous Chelsea football club, which he bought in 2003, and Abramovich is just about as cool as an oligarch gets.
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