PawnBoy developed and shared his design of a fully 3d printable mITX computer case. It looks interesting but I'm not sure if all parts can be done in one piece. In any case if it's not 100% reproducible, it probably just needs some minor tweaks and it's a good base for further projects.
For all the files look at:
http://www.instructables.com/id/3D-Printed-MITX-Computer-Case/?ALLSTEPS
For all the files look at:
http://www.instructables.com/id/3D-Printed-MITX-Computer-Case/?ALLSTEPS