We found this well-designed solar charger, called the i101 series from iceTECH USA, while we were researching the best solar chargers for USB devices. The iceTech can juice up 99% of all mobile phones or USB interface digital products which have operational voltage of 3.5-5 volts. The Solar battery itself can be charged two ways: 1. using direct sunlight or 2. plugging it directly into an electrical outlet.
Once the Solar battery is charged you can use it to charge other devices such as your cell phone or any iPod. It will charge them at the same time frame as your conventional charger. You can also charge your device when you are out (say, at the beach or the park) by plugging it into the battery and leaving the battery under direct sunlight.