Paolo Ciccone has released a Blender Python program After Effects Exporter for Blender (AEE). Blender is a free open source 3D content creation suite available for all major operating systems. AEE "integrates in the File/Export menu of Blender and it allows you to export an entire animation from Blender to After Effects. You can export the camera, lights, 3D meshes, planes, which will create corresponding After Effects 3D solids, and footage. The Exporter even supports multiple passes."
He also has a 20-minute video tutorial on how to use AEE at Creative Cow, along with the projects files and other docs.