The rice is paid for by advertisements on the bottom of each page (which can easily be ignored), and the rice is distrubuted by the United Nations World Food Program.
Check out the "click daily" section of my profile as well, for more ways to help, simply by clicking on those sites daily.
And if you can, get out there and do something positive for others. It doesn't take that much effort, and you'll feel all the better for it. :)