Gordon Henderson (@drogon) has been busy creating an instructional model of a computer, known as LMC, using his Return to BASIC on the Pi. I can’t begin to understand the technicalities of it at the moment, but here’s what he has to say about it:

The Little Man Computer (LMC) is an instructional model of a computer, created by Dr. Stuart Madnick in 1965. The LMC is generally used to teach students, because it models a simple von Neumann architecture computer – which has all of the basic features of a modern computer. It can be programmed in machine code (albeit in decimal rather than binary) or assembly code.

More information, including installing it and how to use it, are available on his website.