If I join, I might actually use Google Sheets. I built a project that used it extensively recently. I would have to see if I could build a compatible system for the engine I use first.
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Google sheets has an open source API. Sending and receiving data is as simple as under 10 lines of code from it. It's available for Python, JS, and multiple other languages. Since I know how to do it in Python, and it's not available in the language I usually code in, I'd have to see if I could run a Python file with the new score information and have the sheet update accordingly.