Breville coffee grinders fall into this category, and were impossible to get OEM internal parts for. When mine failed a few years back, I designed a 3D printed upgrade for the main wear-part in their BCG800XL SmartGrinder and it was not too much extra effort to document it on iFixit[0] with ShapeWays[1] as an easy way to get the part. I think there is a lot of room to do this for all kinds of stuff that would otherwise go to waste, and make a little bit of passive income on the side (enough to cover coffee indefinitely in my case).

[0] https://www.ifixit.com/Guide/BCG800XL+Grinder+Jamming+due+to...

[1] https://www.shapeways.com/product/NASLAGCCP/impeller-replace...