Process Explorer

Quite often I find myself asking whether a certain process running in the background is part of the OS, or is it some form of Malware. This is where the Process Explorer comes in.

Developed at Microsoft by Mark Russinovich, it is supposed to solve all my unanswered questions on the system processes running in the background.

I first read about it Watching the Net, via Reddit.

The guys at Watching the Net have a nice tutorial with screenshots and explanations.