Sketchfab
sketchfab.com
A platform for publishing, sharing, and discovering 3D models — viewable in-browser without plugins and downloadable under various licenses.
Why it is useful
The largest community-driven repository of free 3D models viewable directly in the browser, which means no software is needed to evaluate a model before downloading. Many cultural institutions including the British Museum and NASA publish high-quality 3D scans here for free. For game developers, 3D artists, and educators, the quality range from hobbyist to museum-grade is broader than any comparable platform.