Doink (not the wrestling clown) is a fun little site where you can create art and then animate it. However, there is a lot more here then just creating custom animations. There is a whole Web 2.0/collaboration aspect.
When you sign up you can then comment on others people art, share projects, and even use the forum. They do have a strict policy to abide by so no swearing/bullying occurs, but I don't think there is a built in filter (they will remove anything inappropriate and ban the user).
Click here for more info.
Below is an example of my poor attempt at drawing/animating a Mac Mini. (sorry apple ;-)