Yes, it dims down quite low. Also, after your post, I played around with Mobipocket Reader, turning the background color light purple with black text, which makes it very easy on the eyes. A couple of other benefits: I can download directly to the device without the transfer step like on my Cybook, AND the screen can be rotated in all four directions, so you can set it up easel-like on the table while reading, tapping the screen to turn the page. I think I'm really going to like this thing.
