Makerbot Reference Frame

EDIT: Presently I really think this object is unnecessary for Blender. The "graph paper" in the background of Blender is 1mm and if you zoom out 'till the 10x grid shows up that grid is 10mm, and if you zoom out juust a little further you'll be looking at a 100mm box. Fit your model in that and it's cupcake-ready.

One of the difficulties of designing models for 3D printing is a lack of a "frame of reference" to show how big something can get before the printer won't print it. To remedy thi