The single manned airplane Solar Impulse successfully landed after it´s first 26- hour flight! This is a world record, making the outlook for a greener future in the air considerably closer. Using only solar power as energy source, the airplane does not pollute the atmosphere while airborne. The challenge until now has been to collect and store enough energy without making the planes too heavy. Now, the fact that this technology exists, works and is tested with success is a major leap forwards for the possibilities of expanding.
Visit Solar Impulse´s website here. Also, Wikipedia has an informative text about the project.