When lying in bed, I am on the left side, and prefer to sleep on my right side. I don't always sleep very well and often lie awake in the middle of the night for several hours. Reading my Nook helps me go back to sleep; I think it's the soft white light that does it. Anyhow, if I am on the left side of the bed, I can curl up on my right side and read myself to sleep; in that orientation, the light from the Nook doesn't shine on DH at all, so it doesn't wake him.