vsTODOlist is a Visual Studio 2005 or 2008 language extension that allows you to
implement to-do lists for your development projects using color coding and
Intellisense.

A TODO list file is still
- text based
- partially unstructured

vsTODOlist is
- Free
- Customizable.

Screen cast and download at http://www.InCisif.net/vsTODOlist