SPAW Edito

http://spaweditor.com/en/disp.php/en_products/en_spaw/en_spaw_intro

SPAW Editor is a web based in-browser WYSIWYG editor control enabling web site developers to replace a standard textarea html control with full-featured, fully customizable, multilingual, skinable web based WYSIWYG editor. Version 2 adds tabbed multi-document interface, floating/shared toolbars, modular architecture and many other exciting features