Two important notes for all future PS+SP posts before i begin to give some SharePoint specific cmdlets:

First, make sure if you've added any of my "V3/2007" Scripts to your environment to remove them! Functions "Outweigh" cmdlets so you'll be getting "strange" behavior if you load these!

Second, i am doing examples to show you possibilities.  Unless i say "always do things this way" or "never do things this way"--then I’m not demonstrating a 'best practice'.  Please don't assume that I will always show the "best" way--just one option.  I'll happily add any alternatives people suggest.

With that in mind, here are some starter "SP+PS" samples...

1. Get the local farm:

PS> Get-SPFarm

2. Get All details of the farm (default is a limited "formatted" view):

PS> Get-SPFarm | Select *

3. Get all web applications in the farm:

PS> Get-SPWebApplication

4. Get all web applications including Central Administration (CA) web applicaiton:

PS> Get-SPWebApplication -IncludeCentralAdministration

5. Get all site collections in the farm (across all web applications, but NOT including CA):

PS> Get-SPSite -Limit All

*Note the "limit" parameter.  By default we limit to 20 site collections as "listing all cmdlets" can be a 'large' operation that you should be very aware of doing...

6. Use WhatIf to "see what will happen".  No more "run and hope"!

PS> Get-SPSite -Limit All | Remove-SPSite -whatif

7. "Destructive" cmdlets will prompt by default (provided the Environment's "Prompt" defaults have not been lowered!)

PS>Remove-SPSite http://contoso

8. Prompts can be "suppressed" using "-Confirm:$False" (not recommended!):

PS>Remove-SPSite http://contoso -Confirm:$False

*NOTE: "Success" in PowerShell is "No" output.  When an error or warning occurs it will print to screen--ErrorAction, ErrorVariable, WarningAction, and WarningVariable can be used to "script" handling these outputs.