This rig was used for the production of "Mr. Herorbine's Singalong Tragedy", and was developed by Patrick W. Crawford (TheDuckCow).
Watch the 3 music videos here!
It is being released as CC0 or public domain, so you are free to modify and share as you please. You do not have to give credit, but it is much appreciated :)
THE WAY YOU SHOULD USE THIS RIG IS BY LINKING THE GROUP TO THE BLEND FILE YOU WANT TO USE IT IN
This rig uses FK/IK switching controls. The bone "UIrigCont" to the (rig's) right has the control sliders to switch each limb between FK and IK; I typically animate using inverse kinematics for legs and forward kinematics for arms, so this is the default "rest" configuration, but you can of course change it on the fly as necessary.
The bones of the rig are spread over 3 primary bone layers with varying levels of detail. I general would start animating with only the first layer visible, then adding the others to make the finer tuned adjustments.
The head is made to have independent rotation to the rest of the rig; this is a personal choice, as I think it allows to more easily make less rigid "keyframe-looking" animations - but if you want to re-enable rotation, select the neck bone, go to the single bone tab and select "inherent rotation".
The hair is controlled by an IK constraint. Though the hair was never actually simulated in the animation, the model is manifold and should be robust for simulating with minor adjustments.