I really like this feature. I was hoping it would add to the existing screen savers because I really like some of them but I have created a handfull and formatted/tested them on my kindle.
I have tested all of these
on my kindle. BadBarn is my favorite but I also really like the look of the John Calvin image too. The "Book of Kells" images took a lot of tweaking to get the contrast even this good. Wood engravings seem to translate better than woodcuts.
If anybody has a image they would like to get formatted (600X800 8bit greyscale) send it to me at jacksonunit#gmail.com (where #=@) and I will try to hammer it down for you and publish it on my new Kindleunit