Wiki links that work both ways, and a map of everything you have written.
Notes link to each other with [[wiki links]]. Type [[ and pick a note, or
select text and press ⌘K / Ctrl+K to turn the selection
into a link.
Every note shows what points at it. You never have to remember to add the reverse link, because there is no reverse link to add — the backlink is derived from the forward one.
Links in frontmatter count. If a project's owner is [[People/Dmitriy]], that
person's note lists the project.
The graph draws notes as nodes and links as edges. It can show the whole vault or one folder's subtree.
It is most useful for the two things a list cannot show: clusters you did not plan, and notes nothing points at.
A link whose target does not exist is reported rather than silently rendered. Renaming a note updates the links pointing at it.