PencilTest is this cool blog that collects into one spot those pencil tests that are floating around out there on vimeo and youtube and what not.
I love pencil tests because if I stare long enough at them I start being able to see how to do it 2D. Learning to animate on the computer first is tricky, because you can move things before you're eye has developed enough to really see. 2D on the other hand gives you nothing for free, you consider every frame because you have to draw them all. One of these days I'm gonna figure out how to do it.
*found by Carlos Fins (we went through AM at the same time but never managed to have class together, guess we'll just have to meet at some studio some day :)