Fabricator
Make the classic egg-crate model without the Grasshopper headache. Pick a parametric form (dome, vault, saddle, waves, cone, peak) or drop in your own STL/OBJ/PLY — it's raycast top-down into a heightfield and waffled. Set the rib counts each way, your material thickness and kerf, and the ribs are notched half-depth where they cross so they slot together into a rigid lattice.
Runs entirely in your browser — nothing is uploaded. Export a nested SVG cut sheet sized in real millimetres (hairline = cut), with parts labelled B# / A# for assembly; import it into Illustrator or your laser software at 100%. Slot width = thickness − kerf for a snug press-fit.