hierarchical notebook(hnb) is a curses program to structure many kinds of data in one place, for example addresses, to-do lists, ideas, book reviews or to store snippets of brainstorming. Writing structured documents and speech outlines.

The default format is XML but hnb can also export to ASCII and HTML. External programs may be used for more advanced conversions of the XML data.

Features:
check-box trees with percentages and priorities
searching
command-line interface
no limit on nesting depth (well the display of a 10 levels deep nested node gets kind of eeky)
in-line editing/single pane
Executing external commands for http:// URLs and email addresses
Spell-checking by using ispell or Aspell
autosave

export filters
ASCII
OPML
HTML (both using unordered lists, and CSS22)
postscript
native XML format
general XML (when working as XML editor)

import filters
ASCII
OPML
native XML format
general XML (when working as XML editor)