At www.freerice.com you can play a word game and improve your brain while doing good for others. Each time you choose a correct definition for a word, 10 grains of rice gets donated to the UN World Food Program.
Do they actually count the grains? How much of the rice actually gets to people who really need it? Don't know, but on my first round, I donated 160 grains of rice before not getting "plumbism". I'm not telling you the answer - you have to do this yourself.