Here's a quiz on how much you know about the population of the countries in the world (all based off data from http://en.wikipedia.org/wiki/List_of_countries_by_population):
 
 http://www.proprofs.com/quiz-school/story.php?title=world-populations_1

I created the quiz because after perusing the raw population data, I realized I had/have a lot of misconceptions about countries and their populations. Tell us what score you got!