It is difficult to go more than a few days at the moment without reading something about 3D printing. Everything from body parts to food can now be printed. I even read just this week that it is now possible to print an entire house. 3D printing seems to be the next "big thing" and will revolutionise manufacturing, and, whilst it may not replace mass manufacturing any time soon, for small runs or niche products it will be mainstream before we know it. So, this got me thinking: haven't we been here before?