Okay, I am fully aware that members aren't allowed to post topics on other websites, especially not in general, but I'm going to go ahead and call out this one as an exception. It's one of the best sites I've ever visited.
Free Rice is essentially two sites in one: a quiz site and a charity site. The main interface of the site is a difficult vocabulary quiz where they give you a word and four choices as to what it means. They start out with some questions of varying difficulty to assign you a "level" from one to fifty, iirc. Each three questions you answer correctly moves you up one level, and each incorrect answer demotes you one. It's really simple and fun, and you learn a lot of new words. I usually start around level 40 and drop down to about 38 or 39. I've never been higher than level 44.
Now here's the good part. After each question, the page refreshes with another question. There are ads on the bottom of the page, so every time you answer a question, the site receives ad revenue which it uses to purchase 10 grains of rice to donate to the world food bank. I've won almost 4,000 grains in the last two days. It may not seem like much, but the more people who play the game, the more rice gets donated. More than 75 million grains were won yesterday, and overall almost a billion has been won.
Basically, this site is a GREAT way to spend a few extra minutes. You get to have fun, learn, and help out just a little for ten minutes every day.
www.freerice.comProps to ASofterWorld for bringing this to my attention.
EDIT: doktormartini i see you viewing this topic go win some rice