Well, I didn’t design it but I built it on the MbR2.
The part is hosted on Thingiverse at: http://www.thingiverse.com/thing:31994
You can print the whole thing or as 3 pieces then screw them together.
The part did start to pull up the tape so there is a bit of a curl on one section but I think it will be fine.
Personal manufacturing/fabrication is sweet!
Oh, what is it? It slides into the cd tray in my car and holds my galaxy s3. 🙂