Jon Gordon is one of the modern guru's of positive thinking and teamwork.  One of his best-selling books, The Energy Bus, lists the following "10 Rules for the Ride of Your Life"... I like to think of my team as a school bus with plenty of room :)

Steven Covey's famed "7 Habits of Highly Successful People."  Like a tree grows tall and strong from its roots, so does the first of the 7 Habits.  Also, just as the sun and rain perpetually fall upon the tree to breathe life into it, so does the last of the 7 Habits.  I like to think of applying the 7 Habits to how I plan out projects in my life or periods of time in my life... I have learned that you must plan for time off if you want to truly "sharpen your saw."