This plate allows the user to quickly and accurately zero to the corner of a piece of material anywhere on the table.

This 3-Axis Zero Plate works much like ShopBot’s Z-zero plate, but is able zero the x, y, and z axes simultaneously. It comes with a routine that touches off the plate and calculates its corner, zeroing the bit there. It works for both outside corners and inside corners, so you can zero to the outside of a board or to the pocket of a jig. It works with both end-mills and tapered bits. It will even tell you if your work-piece is parallel to the x and y axis of the machine!

 See it in action:
https://www.youtube.com/watch?v=sscowFpmedg
https://www.youtube.com/watch?v=m6pavc93Fo8