Nearest country
As a variation on my map of the nearest capitals, I had a quick look at determining the nearest foreign country for all parts of a country. This is best done on a per-country basis, so here’s a map of Denmark allocated into German, Swedish and Norwegian “sectors”.
I guess the main use of this would be to determine which languages to teach in schools on a regional basis.
However, I’m not sure how useful it is – I guess a large country (such as Germany) will influence a larger area than a small country (such as Luxembourg), so I guess I should build some kind of population weighting into the program, too.