Cell phones, PDA’s, cameras, GPS devices. If it has a USB wall-wart charger, you can solar charge it. This article shows you how to build a solar charger for your USB charged devices. Never be caught with a dead cell phone again.
If you aren’t up to making your own, the Lenmar PPUS20 PowerPort Solar Charger & External Portable Lithium Ion Battery for Cell Phone/iPhone 3G/MP3/USB Charging Cable/Device Tip Adapters is a good choice.