Windows/Linux: It's one thing to be able to quickly search through file names using a program like Everything, but it leaves you out in the cold when it comes to deep searching documents. DocFetcher can help by indexing document contents.
If you need to search within a text document instead of simply searching for the name of the file, DocFetcher is a great application available for both Windows and Linux to do so. DocFetcher doesn't simply index the words and leave you to pick through them, you can use a variety of parameters like including or excluding search terms using the +/- signs, searching metadata, using wild cards and specifying file extensions.
More well known document search tools exist, like Google Desktop, but for those who don't want the bulk or potential invasion of privacy that comes with using software like Google Desktop, DocFetcher is a lightweight alternative. DocFetcher is freeware and available for Windows and Linux. Have a favourite tool for deep massaging your data? Let's hear about it in the comments.