An italian designer/engineer has successfully printed objects using a coffee powder / clay mixture. When fired in a kiln, the coffee burns off, leaving a ceramic material that is light weight and porous. Pacelli the designer is working on trying to print using other organic/clay mixtures as well, in order to create 3D printable material with new properties. Surprisingly the coffee/clay mixture printed quite a bit nicer than the pure clay. Read more about this at http://3dprint.com/8303/3d-print-in-coffee/