Day #4 on the list (that was intended to take a month but will probably take me a year to get through) is "a favorite book."
I'm going with "The Giving Tree" by Shel Silverstein.
To me, this book takes on different meanings at different stages of life.
When I was little, I just liked the story and the pictures.
As I got a little older, it reminded me of my parents... giving and giving and giving. Not always happy with our decisions, but supportive nonetheless.
Now, I even see a theological thread to it - we never think what we have is enough and so we constantly want for more... convinced it will make us happy. God sits around patiently, providing for us, until we finally come full circle and realize he is all we really needed in the first place.
But honestly, I think the book is open for interpretation - if you haven't read it, go get it. And read it to your kids.