Seeing the no-ghosts button reminded me that it's very likely my young kids are never going to have the fun of pushing the "degauss" button on a CRT.

My old and only eReader, a Kindle 3, had ghosting issues, but it self-fixed them by refreshing often. But there's a cost to that, because a full refresh takes significant time. In complex UIs that are more than just text you often can get away with updating only a portion of the screen, at the goat of bits of ghosting. My understanding is that this is still a limitation of this tech.