The Arduino Yun is a great WiFi development board that combines the power of Linux with the ease of Arduino, why would you not want to keep your board safe and sound inside the enclosure? These cases protect your Arduino Yun from things like rogue wires that might short it out while still allowing full access to the board

This is the official Arduino box for the Arduino Yun board. It has a clamshell / hinged construction that allows easy access to the board, and port holes for the LAN, USB and micro USB connectors.