Recursive import of directory structure and specific file extensions into Solution Explorer
Basically, have the ability to point to a folder and specify a few file types (*.cpp, *.h, *hpp) and they get imported in Solution Explorer for the project.
Right now VS only allows you to "Add Existing Files". This needs to be expanded to add existing folders (and all of their contents, including other folders). I occasionally find that a folder in a project was somehow removed from the project, but there is no easy way to readd it!