There is a company that was using graphs to tie together data long before those companies shown "The Brain" was using graphs to join all sorts of different types of information together on a desktop platform at least 15 years ago I don't believe their system is knowing searchable though, although it could be, I have not looked at their offering for more than 10 years now
I used the brain for a bit. It was a very interesting product. Its main issue is that it didn't have a good query language. It would be a cool frontend for Neo4j.
