MocapX is a Facial motion capture app for the iPhone that streams the mocap data to Maya in real-time
Grease Pencil Rigs are a free set of basic rigs for Blender 2.8 that are for use with Grease Pencil. They are aimed to ease the drawing of characters by showing construction lines which you can use for reference while drawing.
AnimChallenge is a Facebook group that features a monthly animation challenge as well as a dedication to learning within the animation community.
Johan The Dog is a free quadruped rig for Maya for use in non-commercial projects.
Advanced Skeleton has been used to rig creatures, props, vehicles and just about anything since 1999. It is free to download but if you want to use it for a commercial project you will have to buy a license.
Grey Matter Gary is a free Maya rig from Squiggly Rigs
The Setup Machine enables Maya users to easily and quickly rig a wide variety of CG characters with just a few clicks. Generate a flexible, modern character rig in minutes saving you days or weeks of work