So, off to ebay I went! I saw a number of really cheap ones marked “BLOCKED BY AMAZON”; I decided not to go for these since theoretically they might have been stolen. In the end, I went for £7 Kindle 4 “non-touch”.

A few days later, it turned up. And I discovered why it might have been so cheap: its stuck in some sort of unquittable demo mode:

This makes me wonder the unit might have been stolen from a retail demo display.

Still, the content of the article is wonderful. I really like the author's marriage of both the hardware and software aspects. I had no idea that an RS-232 interface was exposed off 3 soldier pads inside the unit. That certainly makes it a great place to start, but as the author shows a lot more knowledge (that the author had) was necessary.

A really interesting read!

Very cool! That's a very old Kindle model, though, and I'd be very surprised if any of the methods used are still available on newer models - U-Boot, cracked root password, even a login prompt.