Biped Manipulator – 3dsmax MAXScript, allows to select fast any objects/bones and also the whole groups of objects as arms, legs and spine. Since manipulator uses objects names to select objects/bones it is possible to use it with any rigs systems like Character Studio, CAT, custom rigs etc. Biped Manipulator doesn’t occupy much screen place. If there are several bipeds on the scene it is possible to use for convenience several Biped Manipulators.

Based on Blur's Biped Worker, this script creates a floater interface allowing easier selection of a biped's different body parts. It will simultaneously support several Bipeds with different bone setups. Multi-bone (Control-Click), hierarchical (Shift-Click), symmetry and opposite selections are also supported, as are the setting of commonly use pivot points all within the GUI.

It adds to the biped bend joints on Arms and Legs.
A slider on Hands and Feets control the bend value.
It also can be use to create good twist bones.
It adds the ability to stretch the Arms and legs.

You just have to skin using these new bones and not the biped ones.
But you animate using the original biped bone

Very flexible and fast script to generate a bone based skeleton over the 3ds max's biped. This script creates an entire rig from Bip character. If you don't have time to create all roll bones, and repeat all the same on the mirrored side, just create Bip and set up it's proportions, run the script and magically you will have a brand new rig.

To start, just create biped, custom it in figure mode to match your character. When done, create a new empty layer, select any bip element, and click on script button. Bones will be created automatically on biped structure.