A vigorous torrent of online dawdlers have contributed more than 5 billion grains of rice towards the world hunger relief over the past eight weeks through an enterprising website that has teamed innovation with procrastination.

FreeRice.com, a browser-based vocabulary game, promises to award 20 grains of rice to the World Food Programme (WFP) for each correct definition of English words. Whilst on its inception date of 7 October the site managed to raise only 830 grains, it has since exploded in popularity, and currently raises an average of 350 million grains every day.

The game comprises a database of several thousand words ranging from the commonplace to the staggeringly obscure. The words are categorised into 50 levels of varying difficulty determined by a system that takes into account what people are commonly getting right or wrong. For every three words that the player identifies correctly, the difficulty notches up a level and every wrong answer incurs a demotion. All the while, an onscreen bowl fills up with rice, feeding the hungry whilst nourishing the intellect.

According to the site, "there are words appropriate for people just learning English and words that will challenge the most scholarly professors." It claims that it is rare for people to reach a level of 48 or above.

Professor Randall Stevenson, head of English Literature at the University of Edinburgh and who reached level 46, worth 500 grains of rice, on his first attempt, said: "It gets difficult even after 200 grains or so. I confess I had to phone a friend along the way, or, more accurately, happened to have a conveniently learned friend on the phone at the right moment to help work out what a 'scaup' might be."

FreeRice pays for the rice from the income it generates from companies that advertise on the website through a cost per action (CPA) system. Toshiba, Fujitsu and American Express are among the assorted organisations that support the site and indirectly fight global hunger. In a recent radio interview the site's creator John Breen stated that over $100,000 (£49,000) has been cultivated so far for the WFP in this way.

Breen is no newcomer to internet innovation. In 1999 he established The Hunger Site, a similarly charitable venture which invited visitors to click on a button once per day to donate just over a cup's worth of food to those in need. Over 200 million visitors have given upwards of 300 million cups of staple food on this site to date.

Speaking of FreeRice, Breen stated: "The ethos of this project is to help people do what they all seem to want to do, which is to end hunger. If we all want to do it, let's do it!"

Some have shown to have more zeal on this matter than others. Among the hundred plus Facebook groups that have rallied to Breen's cause is one called Free Rice Helpers which provides a download link for a computer programme that unleashes a 'ricebot' upon the site designed to philanthropically plough the site of its virtual rice by automatically and tirelessly clicking on answers for as long as the computer remains switched on. The group's administrator Ran Amitay explains, "just run it and watch your pile of rice growing. It even "presses" the ads links once in a while so everyone will be happy."