Ecofont is a cool site for saving ink while you print.
Run your document through Ecofont and they convert all letters and characters into ink-saving equivalents. It uses less pixels in the printing process and can save up to 50% in toner ink!
If you find yourself printing a lot, then this might be worthwhile for you. It’s 7 euros for a lifetime license.
Here’s a report they did with an external lab to verify the ink savings. On an HP LaserJet printing with Ecofont yielded 2,131 pages. Printing with Arial yielded 1,141 pages. On a Canon PIXMA, Ecofont printed 166 pages and Arial font printed 111.