I recently had the need to debug some code and was looking for an easy way to generate the call graph of the application. For a given function I wanted to see who its callers were and who the callers of the callers were, etc. Turns out Microsoft has a free tool called the CLR Profiler that does precisely this.  Here is how to use it:

1. Download and run the executable from this URL.
2. Click on "Start" and select "Run".
3. Type C:\CLR Profiler\Binaries and click "OK".
4. Click on ClrProfiler.exe.
5. Click on "Start Application".
6. Select the application you want to analyze.
7. Then click on "Kill Application".
8. To view the call graph click on View and select "Call Graph".

This can also be used to profile the program and to improve and optimize its performance. Also it works with ASP.NET applications. Overall, an extremely cool application.