She-Hulk Rig is a free Maya rig made by @CromaCore_. Download it from his Gumroad page!
Kratos Rig is a free Maya rig made by @CromaCore_. Download it from his Gumroad page!
ProRigs are Maya rigs developed by talented artists from animation studios such as Disney, Dreamworks, Pixar and Sony. Available on a subscription model which gets you access to over 40 rigs.
Animation Methods is a website hosted by animator David Rodriquez and has links to hundreds of rigs, tools and tutorials.
Built By Colossus Rigs are free and paid Maya rigs available for download. Founded and run by Roman Jeffery.
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.