Read on my Nook so the light doesn't wake my husband. Sometimes it works, sometimes not. I've learned that when I can't get back to sleep (like anytime after 2am) it's because i'm either cold, hungry, or worrying about something. If I'm still awake at 4am, I'll go downstairs, get a snack, and do some grading (which is usually what I am worrying about getting finished on time). I usually don't go to bed until 11pm or midnight, so it's an issue if I wake by 3am and can't go back to sleep.