Is a cargo ship partially pulled along by the wind not sufficiently green for you? How about one complete with photovoltaic-covered sails, power-generating fins, and fuel cells? That's the design now being shown around by Wallenius Wilhelmsen, one of the world's biggest cargo ship manufacturers. Although the "E/S Orcelle" is a concept vehicle (i.e., not intended for production in this form), Wallenius Wilhelmsen intends this as a demonstration that efficient, clean technologies are now available for the shipping industry. The E/S Orcelle, if built as a car carrier (its somewhat ironic default configuration), would be able to carry 50% more than current car carrier ships at similar tonnage -- and would completely eliminate the use of pollution-laden ballast water tanks.
(Found via Gizmodo)