Addicting AND good for the world

Play the Free Rice vocab game... every word you get right, 10 grains of rice are donated to feed hungry people. From the FAQ:

Who pays for the donated rice?
The rice is paid for by the advertisers whose names you see on the bottom of your vocabulary screen. This is regular advertising for these companies, but it is also something more. Through their advertising at FreeRice, these companies support both learning (free vocabulary for everyone) and reducing hunger (free rice for the hungry). We commend these companies for their participation at FreeRice.

If FreeRice has the rice to give, why not give it all away right now?
FreeRice is not sitting on a pile of rice―you are earning it 10 grains at a time. Here is how it works. When you play the game, advertisements appear on the bottom of your screen. The money generated by these advertisements is then used to buy the rice. So by playing, you generate the money that pays for the rice donated to hungry people.

Who distributes the donated rice?
The rice is distributed by the United Nations World Food Program (WFP). The World Food Program is the world’s largest food aid agency, working with over 1,000 other organizations in over 75 countries. In addition to providing food, the World Food Program helps hungry people to become self-reliant so that they escape hunger for good. Wherever possible, the World Food Program buys food locally to support local farmers and the local economy. We encourage you to visit the United Nations World Food Program to learn more about their successful approach to ending hunger.