These bookends are based on generative design, which lets you make unique organic shapes optimized for strength and mass.

I made this symmetrical for aesthetic reasons, and I think it looks rather pretty. It has also been designed not to exceed 60 degrees overhang to avoid any print issues, so should print without any support.

Provided in 3MF (mesh) + STEP file formats.

White PETG model here shown scaled to 66%, which I think is the minimum viable size and might be a little too small for some people. Recommend printing at 80-100% size.

Note: Here, I modeled the a load of 20 N on the tip of the bookend to simulate ~4 lb of weight (if it were actually held vertically instead of at an angle). The resulting design has a safety factor of at least 15x if solid ABS, which should translate to plenty of strength even when printed in common plastics.