Evil Mad Scientist has an article on their Candyfab 4000, a home-built three dimensional fabricator that prints large, low-resolution objects out of pure sugar.
3D Fabricator Project: a little dodecahedron, a toroidal coil, and a wood screw (20″ long)
The general idea of our build process– that of stacking solid two-dimensional printed layers– is actually common to most solid freeform fabrication methods. Our machine employs what we believe is a fairly novel low-cost technology to accomplish this: selective hot air sintering and melting (SHASAM).
Check the article for more information about the Candyfab 4000, and Flickr for a collection of images.