I didn't like any of the AVR dragon cases I could find on here, so I made this one. It's a two piece case that snaps together and has holes for screwing the board down if you so desire. There are two different top halves, one with a recessed "AVR" logo and one plain. The part with the logo it somewhat more challenging to print and will require supports. It leaves all of the headers exposed and covers the rest of the board, printing with translucent plastic will allow you to see the indicator lights (It also looks really cool in general). The outer part dimensions are 112mm * 61mm, you'll likely need to scale the .stl file in whatever printing software you use. I used a 4th revision board to line up the mounting holes, they may be different for other models.