You've got to wonder if schoolkids of the future will be toting around their textbooks in the Green Angel backpack. The Green Angel backpack was designed by Leon Zhou as a backpack for a tech-savvy generation of youngsters needing portable power at a moment's notice.
The Green Angel backpack gets its name from the "wings" that cover up its backside. The wings are actually solar panels that gather up the sun's rays and convert them into energy stored in the backpack's battery. Zhou's bag comes with a USB port which slightly limits its ability to charge everything. Still, the backpack is just a concept at the moment, and I would expect a production version to have more versatile USB ports/capabilities. You can check out conceptual renderings of the Green Angel backpack here.
Photo Credits: ecofriend, designboom