- pinboard for managing bookmarks (database of things that may be useful sometime; probably never) & reading list for articles
- I'm testing tagspaces (http://www.tagspaces.org/) for local files organization (mostly tagging research papers and books; didn't like Mendeley)
- cardav & caldav from owncloud for contacts and events
- anki as a memorization tool (spaced repetition) - from languages to my own mistakes (i.e. "lessons learned", so I won't repeat them)
- for insights, notes, ideas, things I've learned & everything else I use personal wiki (media wiki) on localhost. This is the biggest part of my "system", I have there entries like things to buy someday, current project's notes/resources, useful scripts, configuration snippets, notes from books, journeys, analysis of my own behaviour, personal journal, ideas for startups etc. But it's hard to organize, it becomes a mess very easly after some time. Also, I can't use it on mobile (I don't want to put all this on the web, there is a lot of personal info), it takes time to add new thing/entry (I need to think to which page new piece of information belongs etc.).
- simplified version of gtd as a meta-system managing this system and for projects/things to do