The Belarc Advisor builds a detailed profile of your installed software and hardware, including Microsoft Hotfixes, and displays the results in your Web browser. All of your PC profile information is kept private on your PC and is not sent to any web server.
http://www.belarc.com/free_download.html
I find it very helpful
Full Version: Belarc Advisor
CyberiaPC.com Community > Technical Zone > Tech Tips, Tricks and Other Useful Stuff > Freeware Tools, Utilities and Services
Very useful 
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