At times it is necessary to update passwords on service accounts or make other changes and it is hard to keep track of where that service account has been used.  One of the places that they are often used is in Scheduled Tasks.  This script allows you to query a computer for scheduled tasks and see the task name, location, ID and Run As Account. It can then be filtered to show only non-default scheduled tasks with the following command:

PowerShell
Edit|Remove
Get-SchTasks -ComputerName Server01 |  
Where{$_.ID -eq 'Author'| 
Format-Table Computer,Task,ID,RunAsAccount,Location -AutoSize
 
Pipelining is also available:

PowerShell
Edit|Remove
Get-ADComputer -filter * | 
Get-SchTasks |  
Where{$_.ID -eq 'Author'| 
Format-Table Computer,Task,ID,RunAsAccount,Location -AutoSize