Via Atlantic Cities, a description of Baarle-Nassau, which not only straddles the Belgian-Dutch border, it appears to have run into the border at great speed and splattered:
[T]he Belgian town consists of 24 non-contiguous parcels of land. Twenty-one of them are surrounded by the Netherlands. while three are on the border between the two countries and thus share a jurisdictional boundary with the rest of Belgium, if also with the Netherlands and if not with each other.
And get this: there are Dutch enclaves within the Belgian enclaves that are within the Netherlands. And, actually, the main part of Baarle-Hertog is about five miles southwest of the portions you see here, and completely in Belgium.
...[B]uildings sitting within both countries pay taxes according to where their front doors are located. Some shops have apparently moved their doors "as a tax dodge of sorts." Indeed, there was a complicated legal case in which a bank engaged in money laundering had a front door in the Netherlands, but a vault in Belgium.
Road trip! And to Point Roberts, Wash., a little town attached to the underbelly of British Columbia.