If you can't live without your Apple gadget and love the environment than you are definitely going to want to check out the iPower from Mi Suny. The iPower is a solar-powered power pack that instantly doubles the lifetime of your iPhone or iPad's battery.
The iPower comes in three different styles, one for each generation of the iPhone and one for the iPad. The charger can be charged via USB, but it is more environmentally friendly and easier (depending on where you live) to charge it via the sun. Once charged, the iPower has enough juice to recharge an iPhone 4 twice before it needs to be recharged. While the power pack does make the iPhone 4 look a bit bulky, it is worth it as Mi Suny promises 45 hours of extra music playback or five-and-a-half more hours of talk time. If you can't get enough of your Apple gadget you can pick up an iPower for around $111.