Hand-made Cover (Soft & Padded)
I bought an ereader cover sewing pattern for the Nook/Kindle, and with a few modifications made covers for my New PRS-650 and a friend's PRS-600 (I had to make mine a bit smaller than hers.)
I modified it to remove one of the fabric corners for easier access to the SD-card & stylus. I have an elastic ribbon for that corner instead. I also made each corner 5mm (about 3/16" narrower). I also used an elastic ribbon loop instead fo a fabric one for around the button. I think if I make another one, I'll add an elastic ribbon in addition to the left corner over the power button, to make it easier to get to the power button, though the fabric is easy to push aside.
I should have made it another 3-4mm narrower I think, but it works well enough, and looks pretty good. The pocket where I store the cable closes with velcro so that the cable doesn't slip out and scratch my screen.