After having described StyleCop in the blog post Using StyleCop to enforce source code standardization, here I describe FxCop.
FxCop is used to do code analysis of generated dlls.
It is automatically integrated in Visual Studio Ultimate edition. In the project properties, it will be possible to find a new "Code Analysis" tab. From this tab, it is possible to enable Code Analysis on build and eventually define a file for custom rules (like for StyleCop, it is a good idea to use a shared file used by all the projects in our solution).
You can find more details in the following articles: