Relationship between fulfillment and consumption

I discovered this fulfillment curve on a blog that I like to follow, "Not Buying Anything".  Seems to sum things up pretty nicely.  Having more than we need does not increase our sense of fulfillment, and in fact decreases our sense of fulfillment.  Money does not buy happiness, unless it is given away, or helps to meet our basic needs.

How often do we hear of lottery winners, famous celebrities, "successful" business people or professional athletes who are financially wealthy and yet live unfulfilling lifestyles.  Their lives of extravagance tragically often involve broken relationships, drug abuse, depression and sometimes suicide. However those who give generously of their great resources tend to live enriching and fulfilling lives.

What's enough for you?