Freerice.com

Wow, I got turned on to this great site, freerice.com, by GFW magazine's podcast. Basically, it's a vocabulary game. It shows you a word and four answers, one of these is a synonym for the word. The game adjusts to your vocabulary level, so it feels fair. But the cool thing is that for each word you get right, the advertiser donates 20 grains of rice to the United Nations World Food Program.
So you're playing a fun game and helping people get food in third world countries. We need more of these initiatives. I recommend everyone check it out. It's great.
Dave