I'm working on a startup/iPhone app that is tangentially related to meditation. I've been meditating off and on for fifteen years now and as part of the app development I took it up again, as a kind of dogfooding approach. I've successfully used meditation in challenging sport situations (mountaineering, skydiving, swimming) but I've also had moments where everything in my life was going wrong except the meditation. Meditation can help you stay healthy, focussed and relaxed but anyone claiming it will fix your life is a charlatan.