PowerGUI is a graphical user interface and script editor for Windows PowerShell.
You can create your own nodes and script nodes for all kinds of things, but there are also a lot of so called power packs ready for download from the Library on powergui.org for things such as Exchange, OCS, SQL and so on.
When you click on a node, i.e. Processes, you get a list of the running processes on the system, but you can also go to the “PowerShell Code” tab to see the executed PowerShell commands. Great way to learn PowerShell using a GUI!
Also, there is a very good script editor with several features such as intellisense.
For starters, I would recommend having a look at Jeffrey Snover (the PowerShell architect) and Dmitry Sotnikov`s video on Channel9. This is a nice introduction to PowerGUI. Also check out the other great resources on powergui.org
Btw, I`ve written the Norwegian translation for PowerGUI which is included in the latest build.