The Minion Rig is a free Maya rig based on the popular Minion characters from ‘Despicable Me’
Minion Rig (FREE)
Pink Panther Rig (FREE)
The Pink Panther Rig is a free character rig for Maya based on the popular character ‘Pink Panther’
Ultimate Rigs (FREE)
The Ultimate Rigs are great free Maya rigs for practicing body mechanics
Graph Editor Redux
Graph Editor Redux is a redesign of Maya’s curve editor toolset. Not only does it reorganize the classic graph editor functions, it provides new tools that many animators have found extremely helpful in massaging animation performances.
Brendan Body (Birds)
Brendan Body has a great post on his website which displays lots of great reference and observations on birds and flight.
Animators Resource
Animators Resource is a similar website to this one but focuses more on specific posts and videos rather than linking to other websites.
Sketchfab
Sketchfab allows you to upload full 3D scenes for others to view directly in their browser. They are the world’s largest platform to publish, share and discover 3D content online and in VR.
Mixamo Auto-Rigger (FREE)
Mixamo Auto-Rigger is a free online tool that allows you to upload any 3D human model with two arms and two legs and get it rigged with a full skeleton and skinning weights.
Source Filmmaker (FREE)
Source Filmmaker is a free movie-making tool built and used by Valve to make movies inside the Source game engine. It is a full package and can be used to make cinematics using Valve models and environments.
Animator's Resource Kit 