The introduction on the Powershell Wikipedia article is a good overview . Powershell can also be used remotely, and various Microsoft products provide cmdlets (basically utilities) to use from the shell.
There are a few ways of dealing with IIS7:
* Remotely using IIS Manager 
* .NET-style configuration files - think httpd.conf
* Powershell cmdlets
SQL Server has Management Studio in various flavors, SqlCmd.exe or Powershell cmdlets.
The only time I log in to servers is to run installers or when laziness takes hold. These various tools work well enough that Microsoft offers Windows Server Core which only provides CLI access (and Powershell in the most recent version).