WWF has created a special file format that prevents documents from being printed out, thus reducing unnecessary use of paper.

Flo Heiss: “‘Command P, can you print this for me please?’ ‘Hang on, I just need to quickly print this out.’ ‘No, you’re not, because with this you can´t.’ The WWF have developed a file format that you can’t print out. It turns documents into unprintable PDFs: WWFs. Incredibly simple. Amazing. Say goodbye to those piles of paper cluttering the tables and chairs around your office printer that somehow always materialize. This is inspired. Do I need to go on?”