For quite some time I entertained the idea of implementing an emulator. My knowledge of low level programming is mostly teoretical and this would be a good chance to learn more, and also to experiment with optimizations I rarely encounter in my usual machine learning tasks (being based on libraries like Numpy and Scikit-learn which already take care of the heavier operations).

The Game Boy is an obvious candidate, being it a console I had as a kid, well documented and for which there are many existing implementations including a Python one.