This thing that apparently worked very well for that sociologist that mostly likely operated before the iper-connected and mostly digital world that we currently live in (he died in 1998).

It's now being marketed as another holy grail solution, it reminds me of the GTD method back in the day (in terms of marketing).

Index cards and custom sized drawers? lol nope.

To add some constructive feedback: I'm playing with MediaWiki and i noticed this nice links on the right side of all pages: "What links here". It reminded me of this Zettelkasten thing. But without much fuss.