Studies of housing, furniture, construction materials, and the CAD that creates it.
Like many other aspects of design, it was CAD (computer-aided design) that allows us to make decent stabs at architecture from a PC that fits on our lap. Gone are the need for drafting tables and smudged drawings. The best thing about CAD is that you can make changes and try new things.
This is evidenced by many of the designs here. They started as one thing, a tract house, or an entertainment center, and then morphed onto other designs. Each morphing was for something to solve a specific problem.
Even if you don't have a large plotter, the fine folks at FedEx Office (Kinko's) have large-format printers you can use to make huge prints.
The biggest change for me was AutoCAD, which I bought in 1988. I had learned some CAD with ProCAD, a program to draw schematics and lay out circuit boards. AutoCAD was cutting edge at teh time. Release 14 got me so frustrated I bought TurboCAD instead of upgrading to AutoCAD 2000. While TurboCAD was faster and easier to use, it was Solidworks that blew AutoCAD out of the water, at least for mechanical design. For architecture, I still use TurboCAD. With that program, I am stalled at version 15 Pro, since like many CAD companies, they took one product and split it into several. To get all the things I need, I would have to spend thousands of dollars to get a multiple package that can do what my old one does adequately. No thanks.