I'm working on a mailscript in my spare time.
I have figured out how to send mail
This is not yet with a ui, but this is a function you can use in your scripts. This is written with dotnet and maxscript.

This tool is derivated from EchOoo and Multimesher,

I have it since I released these two tools and use it a lot in production, so I think it’s gonna be useful for you.

It’s very helpful to combine multiple animated meshes into one, without loosing their animations and deformations.

Features :

Creates an attachment constraint from one object to another. By default this tool generates a point helper to attach to another object. 

This is useful if you need a locator to follow a deforming mesh such as a point-cached character.