Originally my thought was to design a open world text based adventure game. The immediate problem that I faced was the fact that the microbit only has 25 led lights and I don't have enough space on the breadboard to make an array of lights to turn on/off to display numbers and letters (or the patience to program every single letter/number as a combination of on/off lights). I thought to buy a text display to solve this and before that making the game an audio based adventure game. More problems became apparent when I realized I was 70ish lines in and I remembered the microbit has limited memory. I have the patience to code away but the microbit certainly doesn't have the storage capacity so it would be a waste of time (it reminded me of a interesting saying: "As hardware becomes optimized, software becomes less optimized").
A solution came into my head to have multiple microbits slaved to the main microbit (the controller) and have said controller request for functions to be run on other microbits and have it return only the necessary outputs. This would greatly increase the size but I only have one microbit (this idea was mostly inspired by the Condor Cluster).
At the time of writing this I am rethinking what I want to do. I am debating between a remote controlled vehicle or an arcade like game (both of which will need a few external parts from outside the kit). As I know the microbit has bluetooth, I might use my phone as a controller. Better yet it just hit me as I am writing this, perhaps I could instead of having a legion of microbits I could run all the "heavy duty" code off my phone (by the standards of the project, a super computer) and have the microbit programmed to take and display data. The only problem with this is the figuring it out part so I can't guarantee I will do this as of right now. My plan is to spend a couple of days seeing if I can do that and then determining the feasibility, if not then I will most likely go to building a simple robot, rc car, or arcade like game depending on future thoughts and what I can and can't feasibly accomplish (having the parts available is part of feasibly accomplishing). Condor Cluster article: https://phys.org/news/2010-12-air-playstation-3s-supercomputer.htm