SketchUp's 3D Warehouse offers an extensive, free 3D model library. With enhanced search functionality, real-world products and materials.

Browse 250+ 3d model library stock illustrations and vector graphics available royalty-free, or start a new search to explore more great stock images and vector art.

Turbosquid is probably the largest professional 3D model source online and there are scores of libraries that provide both free and or commercial models such as WireCASE, 3DXtras, and 3D Model ...

Polish 3D printer manufacturer Zortrax announced its Model Library where users can store and share projects. It has also released the model and manual for a printable robotic arm.