This is a text editor that, long ago, was available for the Atari ST.
It has a really remarkable user interface that can really only be explained by demonstration.
Ditch everything you know about word processing and text editors before you sit down with Sudden View. It's, well, shocking. Words fail to accurately describe it.
|-- John Nagy|
A somewhat less elderly version is available for Windows95; it unfortunately doesn't work under WINE .
a very simple, fast, powerful, small, low cpu consumption, highly configurable text editor for text terminals and X.
Outliners - Hierarchical Editors
An incomplete history of the QED Text Editor by Dennis Ritchie
QED is a predecessor to ed and vi, one of the first to use regular expressions.
Fe is a "folding editor" descended from Origami.
Eastern Orthodox Editors - those based on IBM XEDIT
This was originally ZDE, a CP/M and ZCPR-based "clone" of WordStar. It has been rewritten in x86 assembler for use with MS-DOS and its friends. A fast, small, and fairly powerful text editor.
Acme the Plan 9 text editor
If you need to edit files of simply enormous size, and can afford the notion of not having an "interactive" editor, sed provides a quite ferociously fast option. It works via making one pass across the input, which may run numerous edit transformations, which is very efficient.