Check this out from Wikipedia about Free Rice –
“Effectiveness
In its first six months of operation, FreeRice donated over 42 billion grains of rice. One month after the inception of the viral marketing program, users had earned enough points for one billion grains of rice. The United Nation's World Food Programme stated that this amount could feed 50,000 people for one day.[4] Thus, approximately 20,000 grains of rice provide enough caloric intake to sustain an adult for one day. Using this calculation, enough rice is donated to feed about 7,000 people daily.[5] Since its inception, as of March 28, 2010, FreeRice has donated over 80 billion grains of rice. This is enough to provide food for 3,850,000 people for one day.
Scripts
Since FreeRice became well-known through Digg.com and other news sources,[6] many programming-adept users created scripts to automatically play the game for them. The scripts operate far faster than humans alone and run for 24 hours a day. At first, the scripts got only ≈1/4 of the words correct by random chance. Eventually, these bots were adapted with automated online dictionary search, dictionary files, and word database dumps so the programs can choose the correct answers the first time more often. The word database dumps were created so when the incorrect answer was chosen, the bots would record the correct answer the next page would show. Thus, the bot would choose the correct answer whenever it happened upon the same words later. Due to the growing number of scripts used on FreeRice, the number of rice donated has remarkably risen. Currently there are no rules governing "ricebots", as they are called. Until those rules are formed, anyone is free to program and use the scripts. With a delay of about 3 seconds between iterations, it is estimated that a script can feed about 8 people per day, if running 24/7.[7] The idea was taken even further to create a multi-threaded bot which can run fifty or more browser instances at a time, enough to produce as much as 600,000 grains of rice per hour or to feed 720 people per day.[8] One script with 1,000 threads was able to donate over 3,000,000 grains in just a few hours.
Donated rice comes from the advertisements from sponsors. Therefore, abuse of scripts could lead to catastrophe, as advertisers prefer that actual people view their advertisements. Knowing the existence of the bots, FreeRice updated their FAQ explaining the potential damage of botting.[9] Some bots have made changes to make sure they won't spoil the FreeRice spirit.[10]
It could be argued that using scripts could harm name brand support in the long run. If advertising companies realize that the ads are not being read by humans, they might decide to remove their support. This has yet to be seen.”
BZ