Printable box for the Mini Arcade Joystick sold by Adafruit (http://adafruit.com/products/480) and others.
Depending on your settings, the lid should be a press-fit. You MUST print it with support due to the lip. I used Goop to secure the top plate of the joystick to the lid so that I can use a razor to remove it later if needed. See pic.
Mostly I designed this so that you can use the joystick in a stand-alone mode as an addon controller for Scratch.
Also see http://www.thingiverse.com/thing:93901 to print 2-axis and 1-axis limiting plates for this model of joystick.