Summary: Use Windows PowerShell 4.0 function to find USB drives on Windows 8.1.

Hey, Scripting Guy! Question How can I use Windows PowerShell to find how many drives attached to my system are using USB interfaces?

Hey, Scripting Guy! Answer Open Windows PowerShell 4.0 in Windows 8.1 with admin rights, use the Get-Disk function
          to find all disk objects, and then filter for a bustype of USB:

get-disk | where bustype -eq 'usb'