Summary

A bracket to hold your Raspberry Pi (model A and/or B; needs modification for B+) with clips that can be easily attached to a VESA-mount (aka FDMI).
Everything is parametrised, so that it can be easily changed (e.g., VESA-mount value).

Instructions

Wanted a bracket to keep my RasPi in place.

Inspired by one design (see sources), I decided I would use clips instead of screws (since model A/B has a … "strange" placement for screws). And while I was at it, I'd combine it with a VESA-mount; for universality's sake. But since I couldn't find anything quite like I imagined it, I decided to use OpenSCAD to design my very own, first thing!

Starting from scratch, the bracket needs three components. It is composed of:

the VESA-mount (the "cross"),
the frame for the RasPi board, and
the clips (on the frame) that hold the board.

VESA-measurements are trivial, the frame for the RasPi was pretty straight-forward once I found the official measurements for the board; designing (and placing) the clips required taking quite a lot of measurements and juggling with empirical values.

I opted for a(n as) symmetrical (as possible) placement of the clips—and I managed: the ones on the bottom and side are actually mirrored. I wasn't sure whether I wanted/needed a clip at the top; ended up adding (a lone, asymmetric) one anyway.

The last pictures shows four design-stages: the (incomplete) prototype (silver), an alpha (green) with wrong measurements, a beta (white) without sufficient wiggle-room for the board to fit, and the final bracket with a RasPi (model A) clipped onto it!

Raspberry Pi (model A/B) bracket (with clips) for VESA-mount