Warren Buffet writes in Fortune Magazine why he is donating 99% of his assets to charity. His thoughts can be a lesson to us, and this is well worth a read...

First, my pledge: More than 99% of my wealth will go to philanthropy during my lifetime or at death. Measured by dollars, this commitment is large. In a comparative sense, though, many individuals give more to others every day.

Millions of people who regularly contribute to churches, schools, and other organizations thereby relinquish the use of funds that would otherwise benefit their own families. The dollars these people drop into a collection plate or give to United Way mean forgone movies, dinners out, or other personal pleasures. In contrast, my family and I will give up nothing we need or want by fulfilling this 99% pledge.

Moreover, this pledge does not leave me contributing the most precious asset, which is time. Many people, including -- I'm proud to say -- my three children, give extensively of their own time and talents to help others. Gifts of this kind often prove far more valuable than money. A struggling child, befriended and nurtured by a caring mentor, receives a gift whose value far exceeds what can be bestowed by a check. My sister, Doris, extends significant person-to-person help daily. I've done little of this.

[...]

Some material things make my life more enjoyable; many, however, would not. I like having an expensive private plane, but owning a half-dozen homes would be a burden. Too often, a vast collection of possessions ends up possessing its owner. The asset I most value, aside from health, is interesting, diverse, and long-standing friends.

My wealth has come from a combination of living in America, some lucky genes, and compound interest. Both my children and I won what I call the ovarian lottery. (For starters, the odds against my 1930 birth taking place in the U.S. were at least 30 to 1. My being male and white also removed huge obstacles that a majority of Americans then faced.)

[...]

The reaction of my family and me to our extraordinary good fortune is not guilt, but rather gratitude. Were we to use more than 1% of my claim checks on ourselves, neither our happiness nor our well-being would be enhanced. In contrast, that remaining 99% can have a huge effect on the health and welfare of others. That reality sets an obvious course for me and my family: Keep all we can conceivably need and distribute the rest to society, for its needs. My pledge starts us down that course.