I've come across a site called Free Rice - Nice clickable link on the right - where you can increase your vocabulary and earn free grains of rice to feed the hungry. Every correct multipile choice answer earns 20 grains of rice. Now that doesn't seem like much but according to WikiAnswers - How many grains of rice in an ounce - There are 1000 grains in a ounce. So for every 50 words you get correct you "purchase" an ounce of rice for a hungry person.
This is a great way to learn something, help someone and have some fun or relax all with the click of your mouse. So let's all get to clicking and see how many rice bowls we can fill. 1000 grains fills a bowl and I've filled 7 in just a little while. Now that is 7 ounces of uncooked rice that will fill the belly of a hungry person. Click, Click, CLICK.