We work with Arduinos, a lot! The most troublesome part about working with them is finding a good way to mount the board somewhere and keep it safe. For us this often involved things like tupperware and duct tape. Not the best looking, or safest way to secure a board.
So we decided to make the Rugged Project cases for Arduinos. They are machined from rugged and durable HDPE and feature a clear acrylic lid. In addition to accepting your standard Arduino UNO board, you can add an expansion stack that allows you to add shields on to your Arduino board and still keep everything nice and safe.
The design allows easy access to the USB and Power ports on the Arduino UNO. In addition slits in the sides and bottom of the Rugged Project Case allow for easy and clean routing of your wires to and from your Arduino UNO.