http://www.naturalmachines.com/

It may be the final and ultimate niche taken care of

I think this is going to be a pretty significant niche, judging by the number of articles I have seen over the last 18 months or so.  We don't think of it that way, but we extrude a lot of foods already --cake decorating, candies, pastas, etc.  ...And if people will buy automatic bread machines, they will buy this.

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How about 3d-printed dresses?

http://www.psfk.com/2014/10/3d-printing-future-paris-fashion-week.html