I usually work on my programming language lone lisp on my free time but I've been feeling burned out lately.
So I started a new side project: decompilation of my cherished childhood video games. Many Mega Man games, starting with Mega Man Battle Network 2.
I just finished polishing and verifying the early initialization routines, and have already traced various parts of the game's engine. I was surprised to discover that it was a huge state machine of sorts. I want to focus on reverse engineering the saving system so I can write a save editor, and the music system so I can listen to the music.