RP gun

(image from http://www.bbc.co.uk/news/science-environment-22421185)

If you missed it, the worlds first rapid prototyped gun has just been printed in ABS with just one metal part. It had to happen I suppose and still needs to comply with national gun laws but the worry will be where future designs blur a grey area but where the design might serve a legitimate purpose but have a discrete weapon element to it.