Got this site from Digg: FreeRice
Every vocabulary you get right, they donate 10 grains of rice to the United Nations World Food Program (WFP). Interesting concept, but what I found amazing is the vocab training it appears to be. In the style of GRE where you start off easy and as you get words correct, it gets harder, but when you get them wrong, the difficulty decreases. I’ve been stuck around level 28-34 for some time and finally gave up after about 1200 grains of rice.
Definitely helpful for someone who’s planning to take the SAT or GRE any time soon.