There's an article on Yes Scotland's website today about border controls in Scandinavia (or rather the lack thereof).
At first I thought it was a rather pointless article, given that the absence of actual border controls is the norm in most of Europe these days.
However, as the article points out, "for those who travel infrequently, or who usually fly rather than make land crossings, the concept of moving between neighbouring countries without having to show any form of identification, or even stopping at the border, can be hard to envisage."
So to illustrate how easy it is to cross a national border in the EU at the moment, I've found a small video on YouTube showing how to drive from Germany into Denmark:
Will the Scottish-English border look like this after 2014?