This tool can slice selected faces in mesh and poly at any angle with given step.
Usefull in game development for slicing lightgrids or landscapes.
You can use Slice Plane Helper grid for slicing and set your own custom step. It also has 'Hold' function for undoing results.
Just put this file in \UI\MacroScripts\
After starting 3ds Max You will see new item Grid Slice in Editable Poly Object category.