The Wireless Solar Keyboard K750 is a cool green gadget that's priced under $80. It uses not just solar power, but any form of light to stay charged so you'll never have to change batteries. It can even last for up to three months in total darkness without a charge, and it comes with a solar app that provides detailed information on charge levels.
The thin, lightweight keyboard measures 1/3 inch thick and is made from PVC-free materials. It operates on 2.4 Ghz wireless technology and features 128-bit AES encryption, plus a unifying receiver that allows the user to connect as many as six Logitech peripherals. The three year warranty is another benefit of this keyboard, but the downside for Mac users is that it only runs on Windows 7 or Windows Vista operating systems.