In recent years, many tools have been created in the note-taking space. They often market themselves as something like "personal knowledge management tools", "Z

In recent years, many tools have been created in the note-taking space. They often market themselves as something like "personal knowledge management tools", "Zettelkasten" or "second brain". There are just so many solutions now (and it seems like every week someone develops a new one). I keep a list where I note down solutions I see mentioned. In case you are still in search of a tool, here is a short extract containing some of the more popular tools from my note: Obsidian, logseq, roam, foam, org mode, notion, remnote, evernote, dendron, zettlr, tiddlywiki, joplin, devonthink, thebrain, heptabase, scrintal, ... Now I don't know what you are referring to with "sustainable", if you mean finding a note-taking workflow that is easy to keep up for you, then of course that highly depends on your personal needs (method of input, type of content, multi-platform requirements etc.). My advice would be: 1. pick something that works outside the browser 2. pick something that you can sync, and that has a mobile solution for quick notes on-the-go 3. pick something that works on a "future-proof" plain-text format, e.g. .txt files or .md 4. some tools offer spaced repetition integration, either as core functionality, as plugin, or by syncing to a dedicated SRS app like Anki. If you find a way to frictionlessly create SR cards in your notes, that can be a nice way of keeping some knowledge "cached" 5. keep it simple in general, don't rely too much on specific tools or workflows. they will all cease to work/go out of business at some point. 6. If you are going with any solution that operates on a local folder of .md/.txt/.org files, a nice goodie is that you can actually version your notes with git.