What kind of productivity tools do you use, if any?

This is something I obsess about. What tools do you use to keep track of things, in projects and so on? Tasks, notes, calendars, anything to help your mind to remember and learn. I am always curious about new tools people may be using, for task management to note taking. My current tools are: Nextcloud Calendar for basic calendar use todo.txt with KomoDo and ntodotxt Kate text editor for notetaking (using it with snippets so I have quick links and such that way) reMarkable 2 for handwritten notes and journaling, though I don't use it as often as I'd like