Remember the 1980s when the Japanese seemed to be buying up all the real estate in New York and California? Or the 1970s when the Saudis seemed to be buying up all the Rolls Royces and gold faucets in the world?

These days, it seems like the Russians are emerging as the new kings of conspicuous consumption. Roman Abramovich is building what's likely to be the world's largest yacht. Sotheby's and Christie's have now added rubles to the list of accepted currencies at their big art auctions. And in London, the top real estate...