Mikhail Prokhorov, 43, Onexim Group
Perhaps the wildest child of the oligarch set, Prokhorov gained international notoriety when he was arrested at the French ski resort Courchevel in January 2007 and held in connection with a prostitution investigation. Prokhorov was released and cleared, but a spokesman has said that he won't do any business in France until he gets an apology. Prokhorov fell out with partner Vladimir Potanin shortly after the scandal, and their relationship - which further curdled when Prokhorov sold a stake in Norilsk Nickel to Oleg Deripaska - has never recovered.
Next up for his Onexim Group holding company is nanotechnology. Earlier this year Prokhorov reportedly dedicated $150 million to media endeavors, one of which, he announced, is a sort-of Facebook with the acronym SNOB, for Russian millionaires, along with a similarly branded magazine and television property. And who can forget his personal blog, which offers counsel on, among other things, fitness regimens for youngsters? (He suggests nonprofessional acrobatics for 5- to 8-year-olds.)
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