She-Hulk 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.
Alien FPS Rig is a free first person rig for Maya based on a sci-fi theme (inspired by Alien). Made by Guillermo Moreno Alfaro.
Built By Colossus Rigs are free and paid Maya rigs available for download. Founded and run by Roman Jeffery.
BOTW Link Rig is a free Maya rig based on the Breath Of The Wild version of Link (similar to the previously posted Zelda Rig). Made by Christoph Schoch.