A new type of spherical flexure joint based on tetrahedron elements
Flexure joint equivalents to ball-and-socket joints. One kind is even 3D-printable. See the Hackaday post.
Design of large-displacement compliant joints
Shows some designs of translation and rotation joints with a large range of motion and "minimal axis-drift", i.e. movement in other axes.
Flexures keep this displacement sensor in line
A 3D-printed flexure combined with an analog opto-interrupter gives 5 μm repeatability.
ImplicitCAD
A Haskell-based CAD system. I'm not sure how actively developed it is.
Build123d
Python-based parametric CAD modeling software.
There seem to be a lot of nice features. It seems more like Fusion360 than OpenSCAD does, in that you create 2D sketches and then extrude or revolve them into 3D models.
See: Awesome build123d
Design for 3D printing
The Field Guide to 3D Printing in Optical Microscopy for Life Sciences
Paper about 3D printers applied to microscopy. Some interesting projects and observations about 3D printing.