I recently came across your site while looking for a new incarnation of what was the best Personal Information Manager ever. It was semantics-based, in that it placed a lot of importance on how various things were related to each other. Details about the bit between A and B. It also stores ad-hoc metadata about each node and each connection; creating connection and reverse connection-types and node-types on the fly.
The last traces of this software are archived at http://www.macros.koenecke.us/InfoCentral/
This show an example of it in use ( but unfortunately, not in English )
I’m wondering if you happen to know who was the original programmer/software designer of that system and if there is any more newer software that does the same thing.