I attended a lecture given by a Union Station curator about personal 3D printing. Kansas City hosts an annual Maker Faire, where people from all over the country get together to show and sell their 3D inventions. It’s nice to see that inventors/inventorship is still alive. Autodesk 123D is the software of choice for a lot of these Makers. The program is a solid modeler, as opposed to the mesh (hollow) models made with SketchUp, and it’s free. Tinkercad is another popular program, which Autodesk now owns, too. It’s the program shown in the slides below.