InnovaStudio Content Builder (ContentBuilder.js) is a JQuery plugin that converts a <div> element into Editable Area. Unlike other editors, ContentBuilder.js provides you with beautifully designed content blocks, ready to drag & drop. You can even create your own content blocks.
medium-editor-insert-plugin - jQuery insert plugin for MediumEditor (Medium.com WYSIWYG editor clone)
wysiwyg-editor - A beautifuly designed jQuery WYSIWYG Rich Text Editor based on HTML5.
mooeditable - A simple web-based WYSIWYG editor, written in MooTools.
wysiwyg - Want to roll your own WYSIWYG editor? This will help you get started.
A markdown editor.