From Strapya World, the mecca of miniatures that dangle from cell phones, comes this tiniest solar charger (which, unfortunately, only works with cell phones in Japan). The idea behind it is that it dangles from your cell phone to charge it whenever it's exposed to sunlight. You can also charge it at home with the AC adapter. It's more of a novelty item, as it takes 6 to 10 hours to charge up in the sun (though I suppose it could be a life saver in a true emergency). $18 from Strapya.