This case works well for a Arduino Uno R3 that you use to work with breadboards. It is made to store the Uno and work without the top went prototyping. I am also designing shield extenders for it to allow stacking. The last picture in the gallery with the Ethernet Shield & Arduino with an optional top designed for the ethernet shield.
Just print and install Arduino.
All drawings are DWG format drawn in AutoCAD and if you want them please request in comments. They can be used on Autodesk Inventor.
I used Adafruit Rubber bumper 4 pack for feet.
March 3 2014 - Added STL for ethernet shield and top for it.
Please make sure you flip the top when printing.