I have just a single question for the Flat Earthers.  In your model of the world, how can you get the shortest possible distance between multiple cities to be the exact distances we have measured with supremely accurate devices? 

Example: choose one city on each continent, i.e. Paris, Moscow, Sydney, Johannesburg, New York, and Rio de Janeiro (I'm leaving out Antarctica).  To make it even more accurate, choose a single address in each city.  Then, in your Flat Earth model, measure the shortest possible distance between each city and every other city if you traveled in a straight line.  How come the distances in your model don't match with our current measurements?  Or, if you would prefer, please draw a Flat Earth map with all of the continents and cities where all the distances between them match our measurements.  If you don't trust the currently accepted measurements between cities, please take your own measurements, and then make that map.  I bet you can't do it with a Flat Earth model!

And somewhat related...if the Earth is flat, how come if I setup a powerful laser perfectly parallel with the Earth/ground, it will always end up shining on the sky above?  This would only happen in a spherical Earth.