3D print models are grouped into hominids ... A curated selection of premium and free STL files for 3D printing from a community of 70,000+ makers and designers grouped into 7 categories: Toys & Games ...

Some time ago, [Trammell Hudson] took a shot at creating a tool that unfolds 3D models in STL format and outputs ... but is not free and is Windows only. There is also a Blender extension ...