<p>Can anyone recommend any good <strong>add-ons</strong> or <strong>plugins</strong> for <code>Microsoft Visual Studio</code>?<br>
Freebies are preferred, but if it is worth the cost then that's fine.</p>

http://trolltech.com/products/qt/">Qt Cross-Platform Application Framework
Qt is a cross-platform application framework for desktop and embedded development. It includes an intuitive API and a rich C++ class library, integrated tools for GUI development and internationalization, and support for Java™ and C++ development
They have a plug-in for Visual Studio that costs a bit of money, but it is worth every penny.