Played Freerice and earned some rice to help feed someone.
http://freerice.com/ is an interesting idea. Through the website run by the United Nations World Food Program, they promote education and help feed people.
It encourages education by letting you play some simple word matching games. Every time you get a right answer, you earn 10 grains of rice which is given to someone.
You can read more about it here.
What a cool idea, will have to check it out!