Are you feeling competent? Secure in your knowledge? Well, this set of geography quizzes will take you down a couple notches :) For full humiliation I recommend the African nations, or perhaps the Chinese province one...
Now, stop crying, it wasn't that bad. Check out this nice list of online timewasters.
If you don't have enough time to do all the games, then you should probably go here to learn why you should support the 28 hour day movement.
Who knew that Suessian phrasings could be put to the use of explaining everyone's favorite pet owner, Schroedinger, and his is or not is cat. Only Unka Cecil could do it up right.
And finally, Life came up with a list of 100 photographs that changed the world. They only let you see 28 though.