Design Yearbook has an interesting experiment about which typefaces use the most ink when printed. The fat boy on the block is Impact who will happily drain your ink cartridge without a second thought. At the other end of the scale is classic, well tempered Garamond which prefers sips to gulps.

The experiement is ingeneous in that they use standard biros to draw out and colour in large scale renditions of the fonts. This led to a particulaly nice infographic:

While the results are, perhaps unsurprising it is unusual for Comic Sans not to be the villain of the piece.