Frenzie has shown a way to back up the internal sd without opening the device. You can find the information
here and
here. The necessary steps are:
- telnet into the Kobo device (look in the developer's corner for how to enable telnet)
- remount everything as read only (on the Kobo device)
- copy the content of the sd with netcat to your computer.
Frenzie reported that it took 10 to 20 minutes for the 4 GB to transfer. It took me about 5 minutes to transfer the 2 GB from my Touch via usbnet.