Animation is a little used, yet very strong visual cue, which possesses the unique quality that it can be added to most other existing visual cues (like color, shape, size, etc.), without loosing their pre-attentive characteristics.
The NYTimes infographic "How Obama Won Re-election" [nytimes.com] is therefore one of the very few visualization examples that uses animation in a way that it conveys meaningful and quantitative information. Here, the speed and length of the motion of each dot corresponds to the relative strength with which the population of a US county "shifted" from voting Democratic to Republican, or vice versa.
Notably, it is also one of the few infographics that have been featured so prominently on the New York Times homepage.