There may already be an easy way to do something like this but I made a maxscript for using on my brawl entry. Lemme know if you've got a better way though
I've been working on a little sub-d stuff for the first time in a while in 3ds max and one thing that bugged me a lot was trying to set a temporary pivot to align to certain sub-objects.
So I made this script called 'FB Sub-obj Pivot
' which allows you to select a single component on a mesh or poly object and toggle a working pivot onto it. [or alter the object's pivot]
The script is pretty quick-n-dirty and makes lots of unnecessary assumptions :S but I could do more adaptive math whenever i have more time. I figured I'd post it in the meantime if anyone might have use for it
macroscripts or .mcr files should go in ...Program Files/Autodesk/3dsmax20XX/ui/macroscripts/
then restart 3ds max and it'll be available as a hotkey, toolbar button, or quad menu item in Customize->Customize User Interface