The 3-D printer maker Stratasys went so far as to seize a 3-D printer it had rented to the gunsmiths at Defense Distributed when it found out how they were planning it use it.
The specs, from 3-D technology maker RealD, look more like Buddy Holly's eyewear than the old red and blue glasses used in 1950s movie houses, and provide a much more startling experience.