Do you find it annoying to see your colleagues print emails and other stuff unnecessrily when it can be easily read from the monitor itself? Well, they don't seem to care about the "Protect Environment" logo as much as you do. But you don't want to ask them directly as well. So how to discourage people from printing stuff and save some precious trees?

Here is a unique idea from WWF Germany, to prevent casual use of the print button. Since most documents are shared as pdfs, they have come up with a new file format called .WWF that is exactly like pdf, but without the print functionality.

That means a .wwf document can be opened with any PDF reader, but you won't be able to print it.

You can download the WWF software for free from and it’s now available for both Mac and Windows machines.

Once installed, the software will provide a virtual PDF printer to easily convert documents and emails to the WWF format. It will also associate files with .wwf extension with your default PDF reader. So just double clicking on the WWF files will open them directly using the default PDF reader.

Now if you want to send it to a colleague who may not have the WWF software installed, just change the .wwf extension to .pdf and send it over. He wouldn't notice any difference until going for the print button - see example.