The notion of "golden years" of endless leisure is giving way to a new form of practical idealism: real jobs tackling real problems and making real impact. The Encore Careers campaign aims to engage millions of baby boomers in careers later in life, producing a windfall of human talent to solve society's greatest problems. In this 2008 Encore Careers Summit panel discussion sponsored by the Center for Social Innovation at Stanford, panelists share their "encore" journeys, and how they've had the energy to stay professionally vital and active.