Here are two interesting sites I found recently.

 Sculpteo 3D printing site where you can not only upload your design for printing, but also open your own online store in the 3D printing marketplace on Sculpteo.

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Materialicious™ (“shelter, materials and objects”) is a user-submitted visual curation site featuring modern architecture and design, art, craftsmanship, materials and products.

Submit your art or your 3D Design items for feature articles.