I stumbled on a website this evening... and I have to say it's pretty awesome. Simple idea - you go to the site and answer random school-type questions. Get the question right, and a sponsor pays for 10 grains of rice to be given away to someone who needs it. Get the question wrong, and you try again.
The site is called Free Rice - check it out if you're bored!! You can learn something, and help feed the world at the same time (oh, and snopes.com said the site was legit - just fyi).