Automatically Slice Your 3D Model for Lasercutting « Ponoko – Blog
Slicer3 is a handy, free plugin for Google SketchUp that does pretty much what it sounds like. It will take any solid 3D model and turn it into slices that follow the contours of the form.
Not just useful for lasercutting: seems like a good way to make cardboard or plywood skeletons for complex shapes.