This is one of my son’s favorite topics.
The first article came out awhile ago but, has since been in the news again, “Using Kites to Pull Cargo Ships Across the Seas“ by Jorge Chapa courtesy of Inhabitat.
A second article later came out, “Whatever Floats Your Boat” at the Grist. This article also talks about the lastest ship to hit the news about a japanese sailor and his recycled aluminum, wave powered boat.
More information on his boat can be found at the Treehugger entitled “The Suntory Mermaid II: A Wave-Powered Boat” by Michael Richard.