Really great interactive map puzzle where you can check your knowledge, and also see how the Mercator projection of the world can be misleading as you move north/south from the Equator (the Mercator projection distorts the size and shape of large objects, as the scale increases from the Equator to the poles, where it becomes infinite).
The Mercator projection can be useful for giving directions, but when it comes to world maps, the projection doesn't hold up well as you move far north and south. By how much? Give this puzzle game a try and match the red boundaries to their respective countries.
Mercator world map (Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata (1569) via wikipedia.com