I just released a new version of open source Texticize. Texticize is an extensible and intuitive object-to-text template engine for .NET. You can use Texticize to quickly create dynamic e-mails, letters, source code, or any other structured/unstructured text documents using predefined text templates substituting placeholders with properties of CLR objects at run-time.
Check it out on CodePlex at Texticize