Once upon a time, rich people often bought even small things on credit, lest they sully themselves handling filthy lucre. They employed professional investment advisers to manage their money, which might be deployed in stocks, bonds or real estate. Should the need for a loan arise, one's personal banker arranged it. (Discreetly, of course.)

Nowadays that description might apply to the great bulk of middle-class Americans-except it's inadequate. When I go shopping, I pay with plastic, obtaining instant credit from merchants anywhere in the world, even though they've never heard of me. As to investing, no robber baron or trust-fund scion ever had more choices. With a toll-free telephone call or a few mouse clicks, I can put my money in an infinite variety of stocks, bonds, mortgage-backed securities, real estate investment trusts, money market accounts, options and futures, to say nothing of professionally managed mutual funds. The assets held by these investment pools are scattered from New York to Nepal.