http://www.codeproject.com/KB/applications/includefinder.aspx
This is not a VS plug-in but can be a starter for your own tool. As far as I could see it reads VC6 projects only, the newer VS have an XML format easy to parse. What you need out of it are the default include paths so the tool can find the included files. Alternatively you could provide a settings box for it in the GUI as user input.
