If you thought being eco-friendly was just for tree-huggers then you might be right, but it's also for normal people as well.

You too can save the planet as you email, thanks to a keyboard that powers your computer through the movement of your own industrious hands.

Forget the forests, and fight the battle on Facebook, by saving energy with the Dynamo keyboard from Iwantoneofthose.

The science behind the Dynamo is extremely simple. Simply plug the keyboard into any computer and the kinetic energy produced when you type is transferred from the keyboard to the tower of your computer, where it is stored as electricity.

This electricity can then override the mains power and is then used to power your whole computer, meaning that you can unplug the mains and work totally wirelessly.

And of course, the faster you type, the more energy you generate, which means that the harder you work, the brighter your screen and clearer your audio will be.

And - with all the money you save on electricity you could get some cheap flights abroad and take your family/friends/team on a mini-break.

Perfect for the modern office environment, the Dynamo is just the right mix of conscientious and capitalist.

The Iwantoneofthose team says it is looking forward to introducing more green products into their range of office products this year, including the foot-pump powered fan and hemp mousemats.

The Dynamo costs £59.99, but customers can receive £1 discount for any tree they plant before 1 May.