Process Explorer allows you to go beyond task manager and see your processes in a tree structure to see the parent and child relationships, as well as a performance graph. Double clicking a process will give more details about a process, including a list of threads. Processes are color coded, coloring, for example, .NET applications differently than others. With Process Explorer, it can be seen that a Silverlight application brings in quite a few dlls from the Silverlight directory. Opening the threads window will show you the CPU cycles and memory usage of the app. On-the-fly stack traces are also available.

The successor to FileMon is Process Monitor. Process Monitor is like FileMon, and throws in some new capabilities. Basically, it captures a trace of all file system, registry, and other activity on your machine. The big problem with this is filtering out the noise of the massive amounts of activity. With the filtering capabilities brought up at launch, you can look at only the information you want to see.