Yes. PowerShell, PowerShell, PowerShell a thousand times. I think that every .NET developer should be functional in it. PowerShell can do everything they already know from the .NET BCL, AND run every command line tool they've ever used, AND every server administration task you can imagine. And it's extensible with .NET. I've personally witnessed some pretty awesome one-click deployments with PowerShell, including to Azure with zero-downtime using the MS-supported cmdlets.