emacs
Org-mode is a mode for keeping notes, maintaining ToDo lists, and doing
project planning with a fast and effective plain-text system.
Org-mode develops organizational tasks around NOTES files that contain
information about projects as plain text. Org-mode is implemented on top of
outline-mode, which makes it possible to keep the content of large files
well structured. Visibility cycling and structure editing help to work with
the tree. Tables are easily created with a built-in table editor. Org-mode
supports ToDo items, deadlines, time stamps, and scheduling. It dynamically
compiles entries into an agenda. Plain text URL-like links connect to
websites, emails, Usenet messages, BBDB entries, and any files related to
the projects. For printing and sharing of notes, an Org-mode file can be
exported as a structured ASCII file, HTML, and LaTeX.