I'm not much of a geography nut, but I do use Canada/France as a surprise trivia question for my unknowing friends.

Here's another:

Besides Canada, Cuba and Mexico, what OTHER country border's the United States?

Russia.

And, for my math friends:

What triangle has three (3) 90° angles?

Start at Lat 0, Lon 0; fly exactly north; at the north pole, turn your first 90° to the left; fly exactly south; at the equator, turn your second 90° to the left; fly exactly east; at Lat 0, Lon 0, stop and turn your third 90° to the left. You will be in the exact location you started facing the direction you started in. Three 90° angles.

Still geography, see? :) It's technically called a spherical triangle.

As a sailor/amateur mathematician, this never puzzled me.