If you are a programmer who uses the Windows Search service to index documents on your local computer then this should be useful:
How to register Microsoft Filter Pack with SharePoint Server 2007 and with Search Server 2008
By default, the Windows Search service only indexes content with certain file extensions. Of course they leave out the extensions used in source code. Step #3 from the KB article tells how to add registry keys that tell the Windows Search service to index additional file types. I’ve done this for all of the common .Net file types: cs, aspx, xml. Now, whenever I do a search through Windows Explorer or the start menu, I’ll see my source code in the search results.