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 PowerShell
Part 2: PowerShell for Active Directory
Part 3: PowerShell for Exchange Server 2007
Part 4: PowerShell for SQL Server 2008
Part 5: PowerShell for Windows Servers and Clients

To view the series, visit http://www.idera.com/Promo/Practical-PowerShell/