Get-ChildItem c:\ -r -ErrorAction SilentlyContinue –Force |sort -descending -property length | select -first 10 name, DirectoryName, @{Name="MB";Expression={[Math]::round($_.length / 1MB, 2)}}
Larger than certain size:
$size=500*1024*1024
GCi C:\ -recurse -ErrorAction SilentlyContinue –Force | where-object {$_.length -gt $size} | Sort-Object length | ft fullname