The same platform as Cults above (cults3d.com), reached here via the general homepage rather than a filtered listing: a 3.6-million-design 3D-printing marketplace covering art, home decor, fashion and tools.
The draw is sheer catalog size combined with community proof-of-print photos on individual listings.
Same audience as Cults: people with a 3D printer, laser cutter or CNC machine looking for a specific design.
Both free and paid (including pay-what-you-wish) STL files sit side by side on the platform.
A marketplace with a huge range of downloadable 3D models.