TrulyQuantumChess
A game of truly quantum chess, with interference, entanglement, etc.
You can play online in your browser on https://truly-quantum-chess.sloppy.zone. Alternatively, download, build & run your local mongodb and webapp server. For those people who have reached me asking if they can implement their own features: the source code is licensed under WTFPL, which pretty much means that you can do what the f*ck you want with it :) However, if you decide to add a feature or two, please consider sending me a pull request so that I can push your changes to prod.