Changing the personality of your iPod

Another thing to try out on those cold winter nights when it is too dark to cycle anywhere is customising the graphics of the iPod nano and photo with the help of this handy article from Phillip Torrone at engadget. I am looking for a good way to back up the firmware for the iPod photo, ideas anyone? Should be a dd command from cygwin with the appropriate values for blocksize and count and the usb driver running... haven't quite sussed this out yet.

Good clean fun for all...