PowerShell Scripting: Low Disk Space Notification

Update 20150812
You'll see in the below comments that I left a global variable that was not required in the original script. The below post has been updated with that variable removed.

Original Post
So, I came across a need to have a script that checks the free space of a hard drive, calculates the percentage and send an e-mail notification of the free space is less than 10%. I figured that this could be scripted with PowerShell and run as a scheduled task in Windows. One thing I did find out is that I needed to create a service account in Active Directory with Server Admin permissions. Once you have that account in place simply copy the script below and name it "WhatYouWant.ps1" and set your Windows task accordingly. Disclaimer: I did reach out for assistance with creating this script on StackOverflow. My original script was writing the output to a text file, and copying the contents of that text file into the e-mail notification. This was not acceptable for the long term. You can check out that thread here.

Here's the PowerShell script:

# Set Global Parameters
$emailTO = "SomeOne@SomeDomain.com"
$emailFrom = "SomeOne@SomeDomain.com"
$smtpServer = "SMTPserverInfo"

$computers = ("server1","server2","server3","server4")
$i = 0

# Get Drive Data
$report = @(
foreach($computer in $computers)
{
$drives = Get-WmiObject -ComputerName $computer Win32_LogicalDisk | Where-Object {$_.DriveType -eq 3}
     foreach($drive in $drives)
     {
          # Calculate Free Space
          $obj = new-object psobject -Property @{
               ComputerName = $computer
               Drive = $drive.DeviceID
               Size = $drive.size / 1GB
               Free = $drive.freespace / 1GB
               PercentFree = $drive.freespace / $drive.size * 100
               }
          # Monitor for 10% or less in free space and report accordingly
          if ($obj.PercentFree -lt 10) {
               $obj | Format-Table ComputerName,Drive,@{n='Size';e={'{0:N1}' -f $_.Size}},@{n='Free';e={'{0:N1}' -f $_.Free}},@{n='PercentFree';e={'{0:N1}' -f $_.PercentFree}} | Out-String
               $i++
               }
     }
    
}
)

# Send notification if script finds more than 0 drives with less than 10% free space
if ($i -gt 0)
   {
       foreach ($user in $emailTo)
                {
        echo "Sending Email Notification to $user"
        $smtp = New-Object Net.Mail.SmtpClient($smtpServer)
        $subject = "Server with Low Disk Space"
        foreach ($line in $report)
            {
                $body += "$line "
                }
        Send-MailMessage -to $user -From $emailFrom -SmtpServer $smtpServer -Subject $Subject -Body $body
                }
   } 

Edit the above accordingly to your own needs and configure Windows Task Manager to run when you want.