As Scott Shackford noted below, 3D weapons plans are a big hit. Too big for the State Department. Via Forbes:

On Thursday, Defense Distributed founder Cody Wilson received a letter from the State Department Office of Defense Trade Controls Compliance demanding that he take down the online blueprints for the 3D-printable "Liberator" handgun that his group released Monday, along with nine other 3D-printable firearms components hosted on the group's website Defcad.org, while it reviews the files for compliance with export control laws for weapons known as the International Traffic in Arms Regulations, or ITAR. By uploading the weapons files to the Internet and allowing them to be downloaded abroad, the letter implies Wilson's high-tech gun group may have violated those export controls.

Wilson says he will comply with the order. But he points out that given the nature of the Internet, that doesn't mean it will be taken down off of all servers. In fact, it almost certainly won't mean that.

Despite taking down his files, Wilson doesn't see the government's attempts to censor the Liberator's blueprints as a defeat. On the contrary, Defense Distributed's radical libertarian and anarchist founder says he's been seeking to highlight exactly this issue, that a 3D-printable gun can't be stopped from spreading around the global Internet no matter what legal measures governments take. "This is the conversation I want," Wilson says. "Is this a workable regulatory regime? Can there be defense trade control in the era of the Internet and 3D printing?"

I wrote about the very interesting Mr. Wilson yesterday and in December.