I know they use electricity and resources, but I've always loved Christmas lights. They brought me a sense of awe as a child, and they still do. Each year, we go for a walk through a fairy-tale-lit area and also do a drive around to oooooh and ahhhhhh (sometime between Thanksgiving and Christmas, weather & mood dependent). Though we don't do anything elaborate, we always try to add a little something to our front window (and then non-light festivity to our porch) because it's pretty and makes my kids reeeeeaaaaally excited. I won't do our tree / etc until December, but we did our window decor this weekend. The kids were v.e.r.y. thrilled to get something up. It's simple, but happy. And, er, chilly. :D
Thankful for the ever-present wonder brought on by something as simple as lights.