rechargable motion sensor lights. put these in the our bedroom, in the babys room, and in the hallway between the two. two brightness settings. just bright enough that you can see what you're doing but no so startling that they'll wake someone up. one charge lasts a few weeks, then you'll notice them getting dimmer, meaning its time to charge.
Bonus: our elderly french bulldog sets these off in the morning which signals to me to take her out before she pees on the rug.