I've written a small python program which implements a Turing Machine with a finite tape. It has a tape, a head, a state register and a set of transfer functions ("the program"). The difference to a TM is that when the head reaches the end of the tape, a separate state is triggered: 'end of tape left' and 'end of tape right'.
Now, my experimental idea is to have the transition table in memory so that I have a more "complete" virtual machine, along the lines of a Von Neumann Universal Constructor (not quite the same). What is the minimal program that can run other programs in memory? I'm interested in a different structure of a minimal computing machine, where the transition table is closer to a machine instruction set and can be hold in memory. This will certainly bloat the structure - I'm fine with that. This would be something like a minimal machine which implements an operating system.