Eco font is, quite literally, a font that cuts ink usage down by 20 - 25%. It was created by SPRANQ creative communications, a design agency based in Utrecht.
The font has holes in it, and reduces the amount of ink needed to print the basic sans serif letters.
When I first saw eco font my first impression was that I would probably save even more ink and have a better looking typeface by using a hairline font such as Helvetica thin. This is true if we are talking about a display size printout, but we all know how difficult thin-and-skinny-sans-serif fonts are to read at smaller sizes. The lines become so thin that they are hard to see.
The beauty of eco font is that when it's printed between 8 and 11 pt. size the holes are not noticeable. The font passes as a regular type face, and saves expensive toner along the way. Of course when it's blown up to a display size the circles become noticeable, but that's where the skinny-sans saves the day.
Download eco font for free from dafont.com.