First of all, I think I am Legend is a great movie. I enjoyed it, and recommend it.

Second, I agree with the importance of carrying a notebook. I carry one in my left pocket of my pants. I clip a mechanical pencil, sharpie, and pen on the back of it. I use it daily to jot down notes, ideas, recipes, directions, make lists, doodle, leave messages, and light fires.

And that's basically what I'd use it for in an emergency too. Notebooks are just handy little things. As for out in the woods, sometimes it's easier to make your own map.