Retirement can usher into a person and his or her skills, a slow, almost imperceptible state of decay. It comes with the territory; what better way to retain personal vitality and skilled capability than to interact with people who are younger and less skilled? And, as an added benefit, think of what you might learn about today's world through those interactions. If a retiree has the opportunity, TEACH! whether in a classroom or online. I cannot think of any other occupation nor vocation that will provide so many benefits so intimately to so many.