Leaving New York for California, eco-minded Marshall Dostal knew he'd have to get a car, so he decided to get his childhood dream ride—a 1984 Mercedes 300D. Before long, he was mixing up his own biofuel from discarded restaurant grease in his Pasadena garage. With a clean conscience, Dostal was now sitting on drums of excess glycerin (a byproduct of fuel's distillation process), when his wife Megan, a former event planner for Vogue, suggested using the stuff to make soap. The result is Further, a light, foamy soap with a fresh, grassy scent that actually disinfects and softens hands. While it's still powering the Benz in Pasadena, production's since moved to a larger (and FDA-approved) lab. And the grease? It now originates from such high profile chefs as Mario Batali, who then gets bottles of the soap for his restaurants in return.