Very simple one, 278 kb, with realistic steering drive. SketchyPhysics3, keyboard control. Click on the scene button for better view, the camera will follow it.
STL (Stereolithography, filesize: 41 KB), OBJ (OBJ, filesize: 34.8 KB), 3DS (3D Studio, filesize: 22.9 KB), DAE (Collada, filesize: 63.5 KB), FBX (Autodesk FBX, filesize: 75 KB), IGE (IGES, filesize: 299 Bytes), MAX (Autodesk 3ds Max, filesize: 72.7 KB), SKP (Sketchup, filesize: 142 KB), OTHER (Other, filesize: 22.9 KB)