Tri Vital has created a collection of awesome Maya rigs and put them on gumroad for free!
The External World Rigs are a free set of rigs for 65 characters created by David O’Reilly
The Hekaton Rig is a free Maya rig available on gumroad from Luis Perez and Tre Vital
The Mery Rig is a Free Rig project by José Manuel García Alvarez and Antonio Méndez Lora and works with Maya 2013+
The Judy Hopps rig is a free Maya rig based on the character from ‘Zootopia’
Highend 3D is a website that has a bunch of free rigs available to download and ranges from Homer Simpson to Spiderman and more!
The Mathilda Rig is a free Maya rig based on Natalie Portman’s character from the movie ‘Leon’
Engine House Rigs are a set of free Maya rigs based on simple shapes
M_Rigs are a set of dynamic Maya rigs available for purchase that ranges from a panther to a 6-armed humanoid.