to Be Cool or Be Productive?

These are the key elements of self understanding, knowing when to do nothing and when to act.
Lin Yutang's The Importance of Living contains observations of life's simple pleasures and spiritual happiness. His many philosophical quotes in the book include: "If you can spend a perfectly useless afternoon in a perfectly useless manner, you have learned how to live,"
Of course this depends on the person, being productive, improving, relationships, knowledge, skills, health can fill a your down time.

What do you do to fill yours?