Track projects, defects and features from within Visual Studio .NET

PowerTrack Add-In for Visual Studio .NET - Free Single-User Installations

"Axosoft PowerTrack is an Add-In for Visual Studio to help software developers track and manage application defects and features by project. Users of PowerTrack can easily view, add, edit and close defects and features from within the Visual Studio environment."

Also be sure to check out the .NET Framework-based smart client, OnTime Windows:

"OnTime 2004 Windows Edition – Windows application for tracking defects and features for software development and test teams."