Is ServerManager module available on Windows 7?
Solution 1:
To run Server Manager on Windows 7 you need to download and install the Remote Server Management toolkit from MS
Info link: http://technet.microsoft.com/en-us/library/dd759202.aspx
Download link: http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=7887
UPDATE: new OP info
The problem is that Windows 7 is not a server OS and Server Manager is not designed to manage or monitor non-server OSes. You can install Server Manager on a Windows 7 computer, but only for the purpose of managing other server systems. While there may be a hack to get it to work in the way you want, I'm not aware of what that hack may be.
So I guess the next question is: Why?
If you're just trying to see what you can do with Power Shell: This fix will probably take more than just PS to hack together.
IF you're trying to actually manage a Windows 7 computer in a server role: The answer's probably the same as above: If you can hack it, great. Otherwise, sorry.
Solution 2:
Since incorrect answer surprisingly continues to gain upvotes I feel obligated to post my own.
Unfortunately the solution suggested by @music2myear doesn't work.
The workaround for Windows 7 is to use 3rd party script called PSClientManager.
The only gotcha with it is that it's unsigned therefore PowerShell refused to use it. You can disable signature by of the methods described here.
Solution 3:
The ability to use your Win7 Pro laptop to mange Windows servers is the expectation here--and a reasonable one at that. Some shops frown on admins logging into servers for every little admin function (what roles, features, patch level etc.). What about the guy who's doing QA on servers about to deploy to a remote location? He needs to log in to each box (that's stupid)? Installing RSAT on your Win7 client means you should be able to use PowerShell mods (Servermanager) to do BASIC administration, QA, Audit, etc.