GUM (pronounced goom) and TSUM (pronounced tsoom) are the largest, most over-the-top shopping malls in Moscow. Both are reminiscent of the New Russian joke about the two oligarchs: Boris Nikolayevich is walking down the street when he runs into his friend Andrei Ivanovich. "That's a lovely tie," Boris Nikolayevich tells his friend. "Thank you," says Andrei Ivanovich. "I spent...