3D Artist Quaternius, primarily known for creating great game assets, has released a short tutorial that shows a neat rigging technique that involves Inverse Kinematics. According to the author, this kind of rig is intended for animation and not animation retargeting, to retarget animations you would need a rig that doesn't have Inverse Kinematics. This rig can easily be animated by moving the bones. The entire tutorial is just one picture long and you can see it attached above.
Previously, the author had already posted a similar tutorial, covering the hair creation process in Blender:
