Synfig Studio - Just another WordPress site
Spine - Spine is 2D animation software designed specifically for software and game development.
FaceRig - FaceRig is a program that aims to enable anyone with a webcam to digitally embody awesome...
MocapX - Facial Motion capture app Maya and iPhone. With the MocapX animator, you can easily use the iPhone camera to animate characters in real time directly in Maya. MocapX tools enable you to use any custom or production rig as well as any Maya feature.
AnimeEffects - AnimeEffects is a 2D keyframe animation tool based on deformation of polygon meshes.
Animation Paper - Animation Paper is a software package for doing 2D animation.