For a number of years, I built various To-Do (or more accurately To-Done) lists. I would use them for about a year and then just stop, and make something else. I don't currently have any to-do list solution, I'm just using pieces of paper or forgetting stuff. At one point I had:
- A single-page HTML app that saved entries in localStorage in 1 browser (like 1kb of vanilla CSS and JS, barely anything)
- A static HTML website, generated from a folder of Markdown-like raw text, with a CLI build script. Hosted on a public web server.
- A simple linux CLI command that let me check, set, and mark items as complete, build with Node and saved to a JSON on disk somewhere.
And there must have been one or two more. Nothing serious, nothing that stuck long-term, but I probably spent 1-10 hours making these, and then using them daily for a year or a year and a half.
I'm very conscious about time spent automating or building what you want, versus how much real-life time savings or experience boost does it give you. I'll likely make more of these in the future when the itch reappears and hopefully get another year's enjoyment out of whatever little thing I build.