I am a big fan of Resharper, but right now I am at a client who doesn't use it. Today, I accidentally reset my toolbar, so I was going through and adding my settings (yes, I could have restored an old one..)
As I was doing it, I ran across two items I relied on Resharper to handle.
One will remove unused "using" statements, and the other will sort them in your class by namespace.
Here's what they look like:

They can be found in the Edit Menu items.