I was not a fan of my 10th grade English teacher until many years after I graduated. However, one thing she used to say all the time that has stuck with me is this: "No intelligent person is ever bored."

After some years, I've discovered that while it is not exactly true, it is a very close approximation to the truth. Intelligent people can keep their minds occupied nearly anywhere, nearly any time. One habit is to keep books (as well as paper and pen) everywhere - every room of the house, both cars, all the backpacks, at work - any place one is likely to find one's self stranded for any length of time. And oddly, I have never had a book stolen from me, though a few loaners have failed to make their way home.