First, some advice: NEVER climb a tree to escape from a grizzly. They can climb too. So you'll only find yourself fighting a grizzly, in a tree. Now, concentrate please: yes, it looks like an ordinary backpack. But it has a monocyrstalline solar panel on the front. This absorbs the sun's energy, transferring it into an electrical charge which is stored in a power pack, hidden inside. Attach your hand-held appliance (mobile, digital camera, or MP3 player) to the charger and voila: full power whilst you're on the move.

Of course, the Solar Backpack is also extremely comfortable to carry, with ultra soft padded back and a number of buckles that can be fastened to make it easier to on your shoulders. Better still, the Solar Backpack has a number of compartments for your belongings - look here: a divider which you can use to secure folders or a laptop. Plus, a compartment with a Velcro-sealed pouch for loose change and a concealed zipped pouch to store a wallet, phone, or iPod. Turn it over and there's a small pocket containing a rain cover - ideal for protecting the whole bag from wet conditions. Or bat droppings.