This is a stackable Raspberry Pi case I'm working on to allow you to build small clusters of Raspberry Pi's. I don't touch CAD much (I'm an electrical engineer), but I'm pretty happy with this attempt.
I used the dimensions for the Raspberry Pi provided by Gert from the Raspberry Pi forums (http://www.raspberrypi.org/forum/projects-and-collaboration-general/beta-boards-mechanical-data), so it may not be totally accurate yet.
I printed this using a Stratasys uPrint SE in the Configurable Computing Lab at Virginia Tech (http://www.ccm.ece.vt.edu). These guys are awesome / I work here, so I need to give the obligatory shoutout. I have no idea how it would perform on a MakerBot, but it came out pretty well on the uPrint.
Also note, I have made a few modifications between the printed pictures and the uploaded STLs. I removed my name and my lab name, and fixed a few mistakes I didn't catch before my first printing.
Hope you guys like it!