This is my cardboard case design that can be printed on a sheet of A4 cardboard on a standard home printer. I've been working on it for a while, and have finally got around to putting up the PDF. Please keep in mind that I do not have a Raspberry Pi yet, so this is an untested 'alpha' version, and doubtless will need some further adjustments. I would be very grateful for any feedback about how well it fits an actual Pi, how easy it is to cut and assemble etc... Updated versions based on any feedback will be posted further down the thread as I go along.
Link to the first 'alpha' PDF is here.
I did also wonder about doing a 'deluxe' version - perhaps for use with thicker card or for laser cutting - and charging, say 50p for it, which would go to the Pi foundation (if I could set that up somehow). I'd be interested in peoples thoughts on this.
P.S It's called Punnet because raspberries come in a punnet, but also the printout is a net of the case. See what I did there.