Following in the rich tradition of hidden commands in Windows, what are the hidden or not well publicized features in Windows 2008?
As always with these polls, please list one feature per answer.
For other 'hidden features' of other technologies and tools:
Hidden Features of Linux
Hidden Features of PowerShell
Hidden Features of Oracle Database
Hidden Features of Solaris/OpenSolaris
Hidden Features of SQL Server
Hidden Features of IIS (6.0 / 7.0)