DANIEL SUELO LIVES IN A CAVE. UNLIKE THE average American--wallowing in credit-card debt, clinging to a mortgage, terrified of the next downsizing at the office--he isn't worried about the economic crisis. That's because he figured out that the best way to stay solvent is to never be solvent in the first place. Nine years ago, in the autumn of 2000, Suelo decided to stop using money. He just quit it, like a bad drug habit.