free rice vocabulator
if you know or wish to learn the meaning of words such as depredate and poniard, you might enjoy spending a li'l freetime at freerice.com.
for each word that you guess correctly in a little online vocabulary game, the organization donates 10 grains of rice through the united nations world food program. each time you submit an answer, a pop-up advertisement from a firm such as fujitsu or time/life appears in the lower portion of the screen. with each click, these sponsors contribute funds to the united nations to distribute the rice.
of course, such games cannot single-handedly build vocabularies and feed the world. nevertheless, freerice.com seems like a clever and creative attempt to harness webpower for good purposes.