After some surfing on the net i found a really cool site dedicated to maya rigs and since i’ve been using max for several years, and haven’t been able to find a list like that one, i’ve decided to build up a list with the ones i found.
FREE MAX RIGS:
- Big Fat Strong 1.0.0
Author: Sampad Tauhidul Iqbal

Download Here: http://www.creativecrash.com/3dsmax/downloads/character-rigs/c/big-fat-strong
- Iradj Toon 1.0.0
Author: Iradj Khosronia

Download Here: http://www.creativecrash.com/3dsmax/downloads/character-rigs/c/iradj_toon - Bee-Boy MAX 1.0.0
Author: Ravikanth Reedy (Based on a Maya rig by Rodrigo Ribeiro)

Download Here: http://www.creativecrash.com/3dsmax/downloads/character-rigs/c/bee-boy-max - Judge Rig with facial morph 9.0.0
Author: Ash Chauhan

Download Here: http://www.creativecrash.com/3dsmax/downloads/character-rigs/c/judge-rig-with-facial-morph
If you’re looking for Maya rigs, please go to this site: http://animationbuffet.blogspot.com/ they have a very good list of free rigs for Maya.