I have collected a number of rigs to look at. Some of which I have used to animate and some just to see how they function. I will list some of these rigs here and some of their identifying features.

- Can switch gender and clothes via attributes.
- Limbs can be stretched
- Facial controls that more than one aspect of an object, i.e…
- mouth slider can control shape of mouth and jaw rotation
- brow slider can control elevation of eyebrows but sliding to the left or right controls which eyebrow is affected more
- Ability to control where elbow/knee controls are parented to (either part of the rig or the world)

- “Breathing” attribute that deforms chest
- Help toggle that displays text around some controls explaining how they work
- FK controls have hidden nodes to help prevent gimble lock
- Facial UI looks like a face, moving the controls also deforms the control’s shape
- Eye aimer control can be locked to world, moving eyes also moves eyelids and parts of the face

- Multiple attributes allowing you to change the default shape, size, gender and proportions of the character model.
- Facial controls placed directly on the face
- Squash and stretch options for limbs
- Scaling options on many limbs (a tiny head is amusing to me)