Love your planet? Well, we all do. So let’s try our best to contribute. First ensure that you don’t need a ‘hard’ copy of the document, then just go ahead and print it in WWF. Once you do that, the electronic document cannot be printed (in paper) anymore. Currently available for Mac OS X, Windows version is coming soon.
“The WWF format is a PDF that cannot be printed out. It’s a simple way to avoid unnecessary printing. So here’s your chance to save trees and help the environment. Decide for yourself which documents don’t need printing out – then simply save them as WWF.”