Exchange 2007 has implemented a Get-Tip cmdlet which emits a tip of the day.  Flaphead has written a small script which gets them all and has published them on: http://blog.flaphead.dns2go.com/archive/2006/08/17/3514.aspx. 

There are a number of general tips along with the Exchange tips.  Here is an example:

Tip of the day #29:
Tab completion reduces the number of keystrokes that are required to complete a cmdlet. Just press the TAB key to complete the cmdlet you are typing. Tab completion kicks in whenever there is hyphen (-) in the input. For example:

 Get-Send<tab>

should complete to Get-SendConnector. You can even use regular expressions, such as:

 Get-U*P*<tab>

Pressing the TAB key when you enter this command cycles through all cmdlets that  match the expression, such as the Unified Messaging Mailbox policy cmdlets.

Jeffrey Snover [MSFT]
Windows PowerShell/Aspen Architect
Visit the Windows PowerShell Team blog at:    http://blogs.msdn.com/PowerShell
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