If doing hands-on, helpful construction work appeals to your social conscience, swing a hammer, carry some lumber, and otherwise help build a home for a poor family. Habitat for Humanity is a nonprofit organization that works in tandem with volunteers in communities worldwide to build houses for low-income people. (Former president Jimmy Carter and his wife spend a week every year swinging hammers to help erect affordable shelters for the poor on behalf of Habitat for Humanity.) If you believe you could be doing more to help the less fortunate, then grab your hammer and work up a sweat working with Habitat for Humanity along- side people like yourself.