If you actually print any webpages from the browser, this is a MUST HAVE add-on/extension for Firefox or Chrome (other browsers are supported as well).
Looks like this has been around for couple of years now.. bummer! I wish I had known about it earlier and I would have saved lots of papers and have printed more reading-friendly web documents.
Go check it out and install the extension for your Firefox or Chrome. For Internet Explorer, Safari, and iPad/iPhone, click here then select your browser type and follow the instruction.
You won't regret it and won't be able to go back to your normal printing.
Below is the demo video on how this tool works from their website but if you install the extension for your browser then you can invoke this amazing feature from any web pages! Enjoy! and go green