Shapeways - Shapeways - 3D Printing Service and Marketplace
3D Hubs - Airbnb for 3D printing
Zazzy - Design and sell your own 3D printed jewelry
i.materialise - i.materialise is an online 3D printing service, community and marketplace.
Growmax.io - A smarter, simpler B2B eCommerce Platform for manufacturers, wholesalers.
trinckle - An online 3D printing service provider in Germany. With a software platform paramate.