There is an initiative for crowd-funding open source 3d printed .22 caliber weapons under the name Defense Distirbuted . It aims to develop singe disposable use small caliber pistol for personal defense.
This project will certainly bring out interesting debates in both open source and 3d printing community and get under spot light of mainstream media and law.
UPDATE: project promoters tried to get funding trough Indiegogo, but Indiegogo canceled their campaign.
UPDATE2: they received 20000$ in bitcoin, leased the 3d printer but the company canceled their lease. http://www.wired.com/dangerroom/2012/10/3d-gun-blocked/
Similar concept was used in World War II with FP-45 Liberator mass produced single shot pistol which was simple and cheep to produce and was used by resistance movements.
What do you think?
This blog is in no way affiliated with people who work on this project, and does not support the idea. Information presented here is just news related to the development of 3d printing technology applications. Don't try this yourself, it is dangerous.