Something I really like doing is free charity stuff. It only takes a moment of your time, and you can do it once a day. Just click on the buttons on the following websites:-
The Hunger Site
The Breast Cancer Site
The Child Health Site
The Literacy Site
The Rainforest Site
The Animal Rescue Site
Sign up to any of the above to give even more!
South American Rain Forests
Homes Of Endangered Species
U.S. Wilderness
Coastal Habitats
Reduce Pollution
Sign up at the Ecology Fund and they'll save even more!
Care2.com also has a whole load of them, and if you want to keep track of how much you're saving, register with them. They also have really fun eCards which are free to send and also generate money for charity!
You can also donate money to charity simply by using this search engine once a day. Sign up with them to make sure the money you generate goes to the charity of your choice!