Recently I had to rig a model that consists of a bunch of little parts. It was modeled in Maya and than exported through obj to XSI, so all pivots were feezed – set equal to world coordinates. I made a set of script buttons (insiped by this video) and it saved me a whole lot of time, really.
Note that all of the buttons are freezing Modeling stack. It’s done because they create Center operator there and it notably slows down interaction with the scene – especially if you have to deal with a bunch of objects to align. If you don’t want them to freeze Modeling, just remove
FreezeModeling(null, null, null);
lines from the scripts.