Starseed Pilgrim is a game that involves growing colourful, tree-like structures in unpredictable ways. Fun and highly recommended, by the way!
You can only see a small area of the world at any given time, and after a while I wanted to see the big picture. Being a small game, there wasn't any existing utility that I could find for this, so I wrote my own. Required a bit of reverse engineering of the save file, and yielded some pretty little maps of the coloured blocks I grew over the course of my game.
Also helped me cheat, of course.
Spoiler alert: maybe don't check out my rendered maps until after you've played the game!
Future plans: This was a pretty quick one-off. But I'd love to try this with other games. I did a quick one for Terraria at one point, and a much more extensive one for Minecraft. Who knows... Dwarf Fortress, maybe?