Umbraco CMS

Umbraco is an open source asp.net CMS content management system that uses mssql to store data. Using Umbraco, designers can create valid XHTML markup templates and developers can create any .Net-based module.
Key features include:
Beautiful, user-friendly interface (supports multiple languages)
Comprehensive WYSIWYG editor (can create various types of controls)
Supports editing in Microsoft Word  
Full source code available (open source)  
Super simple template engine  
Full support for web standards