A little while ago, I wrote a post on Determining which w3wp process goes to which SharePoint Service. I have since decided to create a PowerShell script which encapsulates the entire process into one simple command!
There it is! The script grabs the running SharePoint services, the running IIS application pools and matches them up. Then gets the current performance of each process and includes the RAM (working set) and CPU usage.
The script is called Get-SharePointw3wp and is available in my CodePlex project.