Backup-Path.ps1

function Backup-Path ([System.IO.FileInfo]$Path, [System.IO.FileInfo]$BackupDirectory) {
  if (-not ($Directory = Get-Item -Path $Path -ErrorAction SilentlyContinue)) { return Write-Warning "Unable to find directory [$Path]" }

  if (-not $BackupDirectory) { $BackupDirectory = $Directory.Parent.FullName }
  if (-not (Test-Path -Path $BackupDirectory)) { New-Item -Path $BackupDirectory -ItemType Directory > $null }

  $ExistingBackups = Resolve-Path -Path "$(Join-Path -Path $BackupDirectory -ChildPath $($Directory.Name))*" | Where-Object { $_ -notlike $Directory.FullName }

  [int]$Count = 1
  while ($ExistingBackups -like (Join-Path -Path $BackupDirectory -ChildPath "$($Directory.Name)$("$Count".PadLeft(2, '0'))")) { $Count++ }
  $BackupPath = Join-Path -Path $BackupDirectory -ChildPath "$($Directory.Name)$("$Count".PadLeft(2, '0'))"

  $Directory | Copy-Item -Destination $BackupPath -Recurse
  Write-Host "BACKUP: [$($Directory.FullName)] copied to [$BackupPath]"
}