Say Cheese :)

Oxite is the Blogging engine launched by Microsoft.It is a open-source content management platform that developers can use to build sophisticated blogs or large Web sites. Microsoft’s Codeplex team has developed this open source blogging engine. The software is authorized to use the Microsoft Public License way to a fully open source code.

Oxite includes a number of important blog functions that can be complex to implement, according to Microsoft. The framework offers many features common in blogs, including Gravatars, pingbacks, trackbacks, RSS feeds, commenting, MetaWebLog API and an arbitrary page can be output for users to subscribe to RSS. Users can create and edit a series of pages, and can add their own HTML code.
Oxite is a fully-fledged content management service, able to handle not only a blog, but multiple blogs on a single website, as well as large web properties in need of CMS capabilities.
The code consists of around a hundred C# classes, plus some SQL Server tables, DBML and SQL files, and other artifacts. None of the source files contains any copyrights, the code is provided under MPL (Microsoft's Public License)