I did killed mine once unfortunately.
I've sat ot it it the bed.
As a result broken screen and cybook shipped for repair.
Note that cybook was out of the case.
Summary - 1 month w/o cybook and -120Euro repair. It looked that they've replaced not only the screen but also a main board because now cybook has different PID.
Now I've plans to replace hard inserts in the case with something harder like an aluminium sheet.