The NYT piece is focused on the intellectual property issues. But what I sense is the coming of age of 3D printing. As I wrote in a column in November, people will soon be able to download files of physical objects and print them out at home. Although being able to print out a new mug or toothbrush at home sounds magical, I said that there would surely be copyright problems that occur as a result of this technology’s going mainstream. This theory struck oil this week when the Pirate Bay, a notorious peer-to-peer file-sharing Web site that is a source of free copyrighted music and movies, said it was creating a new download section on its site that would enable people to freely take files a 3-D printer can recreate into physical things.