Frustro: The Impossible Typeface
A similar idea, but executed in an even more interesting way can be found in the typeface Priori Acute, designed by Jonathan Barnbrook and released by Emigré in 2010. I urge you to check it out: <a href="http://www.virusfonts.com/fonts/priori-acute" rel="nofollow">http://www.virusfonts.com/fonts/priori-acute</a>