There could be several interesting effects on business and society when 3D printers become widespread, and we've discussed a few of them in the past, including possible crime, for example. But here's another one to think about: Customs Control.
Most countries have some level of customs controls, in which imported goods are inspected for legality and sometimes taxed as well. This approach has worked fine for centuries, but things might get a little different in the near future when citizens have access to 3D printers that can reproduce many types of objects.
In fact, as 3D printers get increasingly capable, the breadth of reproducible objects will only increase. Eventually citizens will be able to obtain many arbitrary objects by printing them instead of having them physically shipped across borders.
But this means the objects will not be inspected by customs control. Objects of questionable legality could spontaneously appear within a country's borders. And they certainly won't be subject to the traditional tariffs and taxes.
The only item crossing a border in this case is the digital 3D model, and it's likely impossible to inspect. We can't imagine a country sealing its electronic borders to perform searches of electronic files.
Could this mean weapons could be "beamed" into another country without the need for smuggling in the future? Could knock-off designs copying brand name items be printed instead of emerging from a manufacturing plant in China? Will cross-border shopping wither?
Due to this and other similar situations, we think an object's design will become a great deal more important as the number of 3D printers increases.