Last week, I heard a story on the radio about a Dutch design firm which has come out with a "eco-font".
The font by SPRANQ, called "Spranq Eco Sans", is designed to save printer toner or ink by including holes in the type face. Apparently they've determined that this saves up to 20% ink when printed, while maintaining the readability of the printed type face.
You can download the font for free from Sprang and install it on your computer. It will then be available for any of your programs to use.
Here's the link to the story from NPR News.