I wanted to be able to produce an SD Card distribution for the Raspberry PI which would emulate the ZX81 "out of the box". On startup an appropriate splash screen would be shown and the pi would enter an emulator. Saving would be via a sync with Google drive.
For the most part, I have followed the instructions here:
http://blog.qruizelabs.com/2014/04/29/raspberrypi-kiosk-matchbox-uzbl/