For 3.75 inch figures, an exterior diorama of the sandcrawler from ANH.
The full model is 62.4 inches wide and 13.8 high (158.4x35cm), but the split version can be used to make a partial model, or just the treads, to save some space.
STL (Stereolithography, filesize: 8.49 MB), PNG (PNG, filesize: 8.49 MB)