Spungella is a blog run by Jean-Denis Haas that is constantly updated with inspiring animations, short films, progression reels and more. A great resource for inspiration!
Spungella
Tea Time Animation
Tea Time Animation is a website and forum run by Lana Bachynski (Blizzard) that has a bunch of great advice and resources for animators.
Pinterest – Animation
Pinterest is a great place for animation inspiration and reference material. Whether you search for animation, dynamic poses or facial expressions you’ll always find something useful.
Animator's Resource Kit 