Kern is for Design Nerds.

A random type-centric word with a missing letter appears at a variable point size. As the leading begins to shrink, you navigate the missing letter to the proper space and release its handle to lock it in place. The placement accuracy is measured and your score is calculated based on the size of the type, the leading height, and the perfection of placement—all measured in points. If you miss by too much and form an unnecessary ligature, one of your five ligature tokens will be lost. Lose all five ligatures and your game is finished. How many points will you Kern?

More info at formationalliance.com and 99 pennies at the iTunes Store