I'm not sure if I'm in the minority on this but I really am not a fan of the case that comes with the cybook. I just don't like the bulk it adds to this tiny reader! I had seen a post in the Sony forums about the Invisible Shield ebook cover and ordered one for my prs-500. When I decided to not use the leather cover I was freaked out about the screen getting scratched and just tried out the invisible shield I had on the cybook. It fits the cybook perfectly and after a few days all the air bubbles worked their way out and its super clear.
If anyone else is interested the link is:
and costs $17.95
I'm thinking of mailing them to see if they will make a whole body cover for the cybook. I have one of those for my ipod touch and it rules!