Finished rewiring and replacing the control board on my Robo R1+ (the first 3d printer i ever bought). It started powering off in the middle of print jobs a few years ago. So instead of replacing the stock board i bought an skr pro 1.2 control board.
The parts have been sitting there for a while but finally spent some time on it this week. Flashed the reprap 6.5 firmware and wired up the tft-3.5 v3 control panel. Just need to finish the tuning and configuration, then it should be printing better than new.
I have another fdm printer(creality ender 3 mqx) and a resin printer(elegoo mars 2). So this was just my 'f around and find out' project printer.
Freespace 2 comes to mind. The whole game engine was open source not just the game itself. Looks like there is still a community building on it too. https://scp.indiegames.us/