Animations don’t need to be long. GreyscaleGorilla.com, a really cool blog and community of artists, has a competition every month called the Five Second Project. The challenge: create a 5 second animation that somehow related to the theme of the month.
Here are some of the winners and honorable mentions from the last few months. Some of these are just awesome.
5 seconds is pretty quick so give it a shot: http://greyscalegorilla.com/blog/five-second-projects/
They take 2D, stop motion, 3d, practically anything that includes some animation.