PowerShell.com and Idera have created a 5 part video series on PowerShell. How you use Powerhell together with Microsoft Server and Client Products.
Part 1: Getting to Know PowerShellPart 2: PowerShell for Active DirectoryPart 3: PowerShell for Exchange Server 2007Part 4: PowerShell for SQL Server 2008Part 5: PowerShell for Windows Servers and Clients
To view the series, visit http://www.idera.com/Promo/Practical-PowerShell/