The SkySail is getting some press, including this graphic from the Telegraph.
The full article offers more:
During the journey from Bremen to Venezuela, the crew will deploy a SkySail, a 160 square metre kite which will fly more than 600ft above the vessel, where winds are stronger and more consistent than at sea level.Its inventor, Stephan Wrage, a 34-year-old German engineer, claims the kite will significantly reduce carbon emissions, cutting diesel consumption by up to 20 per cent and saving £800 a day in fuel costs. He believes an even bigger kite, up to 5,000 square metres, could result in fuel savings of up to 35 per cent.