Here's another tip from my colleague Ed Wilson (the Microsoft Scripting Guy) about how to use PowerShell to
Question: You want to know how many processes on a system are unique. How can you easily find this information?
Answer: Use the Get-Process cmdlet to get the list of processes. Pipeline the resulting objects to the Sort-Object cmdlet and then to the Get-Unique cmdlet. Pipeline the entire results to the Measure-Object cmdlet. This technique appears here:
get-process | Sort-Object name | Get-Unique | measure
Mitch Tulloch is a nine-time recipient of the Microsoft Most Valuable Professional (MVP) award and a widely recognized expert on Windows administration, deployment and virtualization. For more information see http://www.mtit.com.
Ed Wilson is the bestselling author of eight books about Windows Scripting, including Windows PowerShell 3.0 Step by Step, and Windows PowerShell 3.0 First Steps. He writes a daily blog about Windows PowerShell call Hey, Scripting Guy! that is hosted on the Microsoft TechNet Script Center; for more PowerTips check out the Hey, Scripting Guy! blog.