My company just released our latest PR venture today. We've had access to it for a week or so now and I can easily say it's fun, incredibly addictive and still educational. Please give it a go! You can sign in using your Facebook account and everything is completely free. You can even challenge your friends to see who is smarter.
http://www.dkquiz.com/Play over 600 quizzes on everything from Athletics to Zoology on The DK Quiz.
Earn badges, unlock rewards and compare scores with your friends.
I urge you to please notice when you are happy, and exclaim or murmur or think at some point, 'If this isn't nice, I don't know what is.' Kurt Vonnegut