PowerShell snippet to output all colors.

Get-ConsoleColors.ps1

[Enum]::GetNames([System.ConsoleColor]) |
  foreach {
    $foregroundColor = $_
    $backgroundColor = 'Black'
    
    if ($_ -eq 'Black') {
      $backgroundColor = 'White'
    }
    
    Write-Host -foregroundcolor $foregroundColor -backgroundColor $backgroundColor $foregroundColor
  }

Sure makes me wish that Windows had a good 256 color terminal instead of a measly 16 colors.