Toon Boom Digital Pro is the only complete paperless animation software. Designed for professionals and freelancers alike Toon Boom Digital Pro offers high productivity with low operating costs. Based on our Emmy award-winning technology, Toon Boom Digital Pro combines superior vector technology for content creation, real-time animation and compositing stages, all set in a multi-plane 3D space environment.
http://toonboom.com/products/digitalpro/
You can download the free personal learning edition here:
http://www.toonboom.com/products/trial_dwn