NCover
A code coverage analyzer monitors your code at runtime and records information about which lines of code were executed. NCover shows each sequence point in your application along with the number of times that point was executed. Sequence points are generated by the compiler and stored in the debug information (.pdb) files. A sequence point basically corresponds to a single program statement (often a line of code) in your high-level language.

NDepend
NDepend analyses .NET assemblies of an application and generates design quality metrics. NDepend allows you to automatically measure the quality of a design in terms of its extensibility, reusability and maintainability to effectively manage and control the assemblies’ dependencies of your .NET applications.