I just learned about this "text-to-movie" site called xtranormal.com. It's a very cool and easy way to make an animated custom movie. They provide the animated backdrops and actors, and then you add the script and pick the camera angles. You can make the actors do little animations and facial expressions too.
It can all be done online for free. Or you can pay $5/month for more backdrops and actors. You can also download a desktop version called State. State has even more features. You can make the actors move around. You can create your own custom camera angles. And there are more animations, like dancing. State ran very slow on my Pentium 4, 2.8 GHz laptop with 1.5 GB of RAM. I don't have a great graphics card on the laptop though.
Here is a video I made using the online free version.