Toko Content Editor
Toko Content Editor is a free multi language and multi-user web editor. Commercial version also available. http://toko-contenteditor.pageil.net
Spaw
Full-featured, fully customizable, multilanguage, skinable web based WYSIWYG HTML editor control. PHP and ASP .NET versions available. IE 5.5+ required, other browsers see just a plain textarea [Open Source, GPL]. http://sourceforge.net/projects/spaw
Rte_Multi
Open source WYSIWYG component that can replace all textarea fields in every module for PostNuke, eNvolution and similar CMSes (core and 3rd-party). Only works for MSIE 5.5 SP1+ under Windows [Open source, GPL]. http://sourceforge.net/projects/rtemulti/
of_htmlarea
Cross-browser WYSIWYG editor that currently supports IE 5.5+ and Mozilla 1.3b+ that offers a working demo. Needs OOHForms working with PHPLib [Open Source, LGPL]. http://www.sanisoft.com/ofhtmlarea/
Cfdev Editor
A WYSIWYG HTML editor component that embeds into a HTML form [Commercial, with free developer edition that requires a valid email for download]. http://www.cfdev.com/activedit/php.cfm
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