A Global Tax on Banks?

Could the world levy a global tax on the international financial services sector? Gordon Brown seems to think so. The British prime minister told the Financial Times that "support is building" among the world's leading economies for a global tax, and that he hopes to hammer out a deal at June's G-20 summit in Canada. It's unclear how such a tax might work. Brown has proposed that governments take a cut of bank transactions. He’s suggested that the International Monetary Fund's proposal would differ from Obama's proposed tax on wholesale funding. Brown said that such a tax could raise "a substantial amount of money" for Britain.