"Throughout her life, Alexandra Penney's worst fear was of becoming a bag lady. Even as she worked several jobs as a single mother, wrote a bestselling advice book, and became editor in chief of Self magazine, she was haunted by the image of herself alone, bankrupt, and living on the street--she even went to therapy to alleviate the worry. And then, one day, that's exactly what happened. She had taken a friend's advice and invested nearly all of her...