What do mega-successful business leaders and entrepreneurs like Ray Dalio, founder of Bridgewater Associates, Jeff Weiner, CEO of LinkedIn, and Arianna Huffington, founder of the Huffington Post, all have in common?They carve out time in their busy schedules to meditate.Meditation was once seen as an unconventional pursuit of hippies or the avant-garde, but more Americans are turning to the practice to bring balance and peace of mind to their stressed-out lives.