I am doing a bit of research on different areas (AI, cognition, music psychology, aging...) and have gathered so far a huge amount of information in the form of web links, pdfs, printed books and courses. My interest would be to know whether there are any tools around in order to organize this information and tag it with keywords, tags and notes in such a way that a selection of relevant items can be gathered in order to structure my work and make better progress. As of today I am using The Brain 12 and some self-developed tools. The problem with self-development is the time it takes to define, program, debug and validate own software. The problem with commercial tools as The Brain is that they focus on small-scale, personal solutions of a closed nature and do not allow easy integration with other tools. For instance, I would like to extract information I already gathered in a relational data base, input it in The Brain for good visualization, massage it and export it back to other AI tools that could search for relationships or patterns, at a higher level.
In short, programming all by myself takes too long and distracts from the research. Taking off-the shelf products has the limitation that they are closed and not flexible for real research purposes.
So the question is whether any "open" tools for organizing information are available or under advanced development anywhere, which could be tried out.