[.NET 2.0] Visual Studio Tools for Office
I've been attending a few VS.NET 2005 seminars now, and I'm quite curious about the stuff you can do with Visual Studio Tools for Office. It is interesting to use Word and Excel as clients because users know how to use these tools and the Actions Pane is the perfect place for simple controls to help the user fill in and submit a form or similar.
If you're interested in stuff like this, check out the things available at the home page.