Mycelium

Mycelium reads what you write and quietly links it to everything related you already wrote. No tagging, no folders, no daily ritual of filing things away. Open a note from last March and the sidebar shows the three conversations, two papers and one half-finished draft that touch it.

Every other tool asks you to maintain the structure. That works for about six weeks, then the graph rots and you go back to searching. Mycelium builds the structure from the text itself and rebuilds it every time you write, so it degrades toward useful rather than toward abandoned.

Public beta since June, 900 people writing in it daily. Everything runs locally by default; the cloud sync is opt-in and end-to-end encrypted.