From the Daily Grind, I found out about NProject:
NProject is a software project and content management system mainly for the .NET Framework (and Mono). It integrates a Wiki, an issue management and reporting system, a dynamic project calendar and integration with CruiseControl.NET. It's inspired by Trac (http://projects.edgewall.com/trac/) and other cool projects. It's based on Castle MonoRail, ActiveRecord? and Windsor projects (http://www.castleproject.org/). But most important : it's fun and looks cool!