Full description in Russian language available here http://habrahabr.ru/post/16604/
jsiedit Habrahabr bookmarklet. Just drag link to toolbar or add to favorites
Markup languages are widely spread: bbCodes, wiki markup, Markdown, HTML and others. But it is very inconvenient to edit long texts, because you need to convert all the codes in your own head and imagine how it would look like. At the same time you could find 'Preview' button to see formated text. And here comes a problem. You see a misprint in preview mode and want to fix this typo, but needed to return to the text editor, find a corresponding place between tags. Then press 'Preview' again to continue reading. Do you like it?
With jsiedit you could just select any block in preview mode, add, change or delete any text, and return to the reading. It is very convinient and effective. No more long text in editors, only small pieces are edited, and you choose them yourself.
The project is very young. You could try online example here http://praestans.github.com/jsiedit/lib/example1.html
It is based on the proof-of-concept script (bookmarklet) for habrahabr.ru http://praestans.github.com/jsiedit/lib/habr_bmk.js
Use jsiedit Habrahabr bookmarklet.
Step-by-step image guide is here http://praestans.github.com/jsiedit/lib/jsiedit_habr.jpg