Clay 3D Printing
- https://plus.google.com/communities/109375785524125994679 - good group
- Stoneflower - This one claims to be open source, but has no license information - . Online diagram appears sufficient for replication. Clay extruder head can be purchased for eu 119 . Full extruder system can be purchased for $500 - 
- This guy does workshops and talks on the ceramic printer -  - email included.
- This filament is ceramic - can be baked. Shrinks 20%.