This was my final project for my 2D animation class. The flying bat turned out very well; he actually goes up and down while flapping his wings. The bounce is the funniest part. The super-cuteness made it popular with the class.
This animation was drawn using paper, a pencil, a lightbox, and a pegboard. An x-sheet was used to plan the timing. The frames were captured using a mounted camera and everything was animated in DigiCel Flipbook. It usually wasn't required, but I preferred to make the animation loop seamlessly when I could.