Massively^™

One of the more sophisticated animation tools out there is Blender, a cross-platform, free suite of 3D creation tools. Blender allows a lot of animation tricks that are normally only found in packages costing hundreds or thousands of dollars.

The eclectic, artistic, and highly-animated Jacek Antonelli has released a script, scene and animation skeleton that allows users to create and export high-quality animations from Blender into the BVH format used by Second Life.