I like to keep my using block clean too.
Resharper does this with it's "Optimize usings" feature and much much more.
Although the VS 2005 version isn't ready yet, it's the single best productivity
tool for me in VS.NET 2003.
Chris
I use Poor Man's Resharper®. I comment out all the using directives
and add them back one at a time until it builds again. As you chug
along it whines about each missing one as it finds it. Remove the
comments, rebuild, remove the comments, ...
Another item we use to help developers is to use comments after the
using directive to specify why it's even there, especially if it is
less than obvious. Here's a really bad example:
using System.Windows.Forms; // OpenFileDialog
But you get the gist. This helps the original developer and the
future maintainers manage the project without having to rely on their
photographic memories (considering some done even have film for it.)
[

Anyway, in a standard Window's app that comment would be
redundant, or extremely long, so you wouldn't even bother. However,
that sample comes from a MS Word add-in so it automatically answers
the question why it's there.
Ken Wilson
Seeking viable employment in Victoria, BC