Get-VolumeFreeSpace

Here is an example function to return free space remaining on a volume with associated details. Updated 27/04/2012 to fix mount points.

Usage Examples:
Get-VolumeFreeSpace|ft
Get-VolumeFreeSpace|Select ComputerName,Name,MountPoint,FreeSpaceGiB|ft
Get-VolumeFreeSpace|Where-Object {!$_.SystemVolume}|Select ComputerName,Name,MountPoint,FreeSpaceGiB|ft
Get-VolumeFreeSpace “ComputerA”,”ComputerB” |ft

#http://jongurgul.com/blog/get-volumefreespace/
Function Get-VolumeFreeSpace{ 
    Param([String[]]$Computers) 
    If (!$Computers) {$Computers = $ENV:ComputerName} 
    $Base = New-Object PSObject; 
    $Base | Add-Member Noteproperty ComputerName -Value $Null; 
    $Base | Add-Member Noteproperty DeviceID -Value $Null; 
    $Base | Add-Member Noteproperty SystemVolume -Value $Null; 
    $Base | Add-Member Noteproperty DriveType -Value $Null; 
    $Base | Add-Member Noteproperty Name -Value $Null; 
    $Base | Add-Member Noteproperty MountPoint -Value $Null; 
    $Base | Add-Member Noteproperty FreeSpaceGiB -Value $Null; 
    $Results =  New-Object System.Collections.Generic.List[System.Object]; 
 
    ForEach ($Computer in $Computers){ 
        $Volume = Get-WmiObject -Class "Win32_Volume" -ComputerName $Computer; 
        $MountPoint = Get-WmiObject -Class "Win32_MountPoint" -ComputerName $Computer | Select @{Name="DeviceID";Expression={$_.Volume.ToString().Substring($_.Volume.ToString().IndexOf("`"")).Replace("`"","").Replace("\\","\")}},@{Name="MountPoint";Expression={$_.Directory.ToString().Substring($_.Volume.ToString().IndexOf("`"")).Replace("`"","").Replace("\\","\")}};   
        [String[]]$Mounts = $MountPoint|%{$_.DeviceID} 
        $Volume |%{ 
        $Entry = $Base | Select-Object * 
        $Entry.ComputerName = $Computer; 
        $Entry.DeviceID =  $_.DeviceID; 
        $Entry.SystemVolume =  $_.SystemVolume; 
        $Entry.DriveType = $_.DriveType; 
        $Entry.Name = $_.Name; 
        $Entry.FreeSpaceGiB = [Math]::Round($_.FreeSpace/1GB,3); 
        $DeviceID = $_.DeviceID;         
        $MountPoint| Where-Object{$DeviceID -contains $_.DeviceID}|%{
        $Local = $Entry | Select-Object *
        $Local.MountPoint = $_.MountPoint;
        [Void]$Results.Add($Local);
        }; 
        $_|Where-Object{$Mounts -notcontains $_.DeviceID}|%{[Void]$Results.Add($Entry);}; 
        } 
    }     
    $Results 
}