solar chargers are actually rather interesting. For one thing, they aren't just concepts: they're available for purchase right now -- or at least they are in Japan. They're called SolarFold and SolarFan, two designs that both deliver four panels of spherical-based solar cells, comprised of 1,900 globes each, making them slightly flexible and rather more durable than your average photovoltaic. They're reasonably efficient, too, delivering 2W over USB and, in 10 minutes, are able to charge an iPhone enough to make a 3 minute call. (We'll leave it as a reader exercise to figure out how many days would be required for a full charge.) Both models are available now for ¥22,050 (about $250), but only the fan comes with a cool little tripod, making the decision of which to buy a little easier.