FCKeditor

• Internet Explorer 5.5+ and Gecko browser (Mozilla / Firefox / Netscape)compatibility
• XHTML 1.0 support
• Cut, Paste and Past as Plain Text, Undo and Redo
• Paste from Word cleanup with auto detection
• Image insertion, with upload and server browsing support
• Table creation and editing (add, delete rows, etc) – one of the best systems in the market.
• Skins and Plugins upport.
• Spell checker
• Multi-language support
• Automatic browser detection and customization
• Integration with ASP, ASP.NET, Java, ColdFusion, Perl, PHP and Javascript.

Screenshot Official site