This ABS slab emerged from the Thing-O-Matic in early 2012:
The Zire would power on whenever the switches clicked or that little joystick moved, which happened regularly enough to be annoying.
Mary made a small case that matched the other pouches I carry around:
She made the case to fit an HP48 calculator, but it was close enough for the Zire.
Time passed, the Zire died, I started carrying a Kindle Fire in another pocket, but the ABS slab provided a convenient stiffener between some Geek Scratch Paper and the various pencils / pens / markers / screwdrivers / flashlight filling the available space.
Unfortunately, minus the backup of an electronic slab, the protector finally failed along an obvious stress riser:
I cut a similar rectangle from a sheet of unknown flexy plastic, rounded the corners, clipped the pencils & whatnot to it, and maybe it’ll survive for a while.
The Smell of Molten Projects in the Morning 