MikuMikuDance

MikuMikuDance is a 3D animation program intended for use in creating music videos for Vocaloid songs. However, it has been used for many other purposes.

The program comes with a pack of 3D models of the Crypton Future Media Vocaloids (Miku, Kaito, Len, Rin, and Meiko). Other character models can be created and shared by users.