The silhouette of this famous woodblock print from early 19th century Japan is used for a simple shelf carrying two wooden panels (or mirrors in my case). The gap in the larger "wave" is 22mm high, so anything that fits in there is usable. The back of the large wave features 4 cutouts for HP41c modules and one for the TULIP4041. The height of the smaller wave is 85mm, which is also the gap for the bottom row of calculators. You may also use the small wave only for your shelf, the two parts can be combined. The gap on the first "floor" of the shelf is also 85mm. The second floor on top can carry larger things. I am printing this in recycled Prusament PETG with 5% (large wave) and 10% (small wave) cubic infill. Some parts of the outer shell did not turn out well, but that's the way it is. I know this is very special, and there are probably less than 5 people on the planet that are interested in this. Therefore, I include also my FreeCAD file for you to modify. You can remove the slots for the HP41 modules, change the gap between the panels, whatever. As the original print is public domain, there should not be any problem with a license.