Getting Logged on User
A small script which can be used to find what user is logged into a station. Can be handy if you are looking for a station that does not have any user logged into it.
If filters out known SIDs and I have left the MS article in the comments if you need to add more to it.
Using it is as easy as loading the cmdlet:
Get-LoggedOnUser -ComputerName Some-Computer
It will accept values from the pipeline too, so if you are working on a domain:
Get-ADComputer SomeComputer | Get-LoggedOnUser