There's something so tantalizing about ideas like brainfuck. Depending on your skill level, you can easily make a solid implementation in maybe an hours time.

There's something so tantalizing about ideas like brainfuck. Depending on your skill level, you can easily make a solid implementation in maybe an hours time. But once you figure that out, you now have a playground to do things like you're describing on. Optimize execution, map it's memory to a graphics display or network card, build an assembler, etc. Whatever weird stuff pops into your head. I don't know how useful it ultimately is for most people, but for myself I've always found this stuff an interesting learning tool to spring-board off of.