In Visual Studio there is a feature called Annotate. In the Solution Explorer just right-click on a source code file and select Annotate. The result will be a view of this file where you have meta information for each line of code:
- who did the latest change
- when was it done
- which changeset contains this modification
This can be useful in a code review or other situations where nobody remembers (or wants to remember ;-) who did the modifications.