Greg Foyster used to be an ad man, until a chance viewing of  An Inconvenient Truth opened his eyes to the effect his profession was having on humanity, and the planet in general. He abandoned advertising and wanton consumerism, and hit the road with his girlfriend Sophie on a cycling trip from Melbourne to Cairns, visiting others who've decided to live simply along the way.
His book about the trip, Changing Gears: A Pedal-Powered Detour from the Rat Race, is an entertaining and honest look at the challenges of living a life outside of social norms.