Who decided banks had to be all things to all customers? Weill did. Starting with a low-end lender in Baltimore, he cobbled together the first great financial supermarket, Citigroup. Along the way, Weill's acquisitions (Smith Barney, Travelers, etc.) and persistent lobbying shattered Glass-Steagall, the law that limited the investing risks banks could take. Rivals followed Citi. The swollen banks are now one of the country's major economic problems. Every major financial firm seems too big to fail, leading the government to spend hundreds of billions of dollars to keep them afloat. The biggest problem bank is Weill's Citigroup. The government has already spent $45 billion trying to fix it.