Rocket Retriever 

Rocket Retriever indexes your hard drive's file names, and lets you search for names (or partial names) as you type. Find files fast - missing, misplaced, or even renamed. Includes syntax highlighting and pattern matching for easier searching.
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XchangeCL 

Need to change some text that could be in hundreds of text files? Well XchangeCL can make this easy for you. It will find files using wild cards and find and replace multiple strings in each one.
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ShowSize PE 

Unique Explorer style software reports sizes and numbers of folders and files. It can also help you find files not used in many days and can produce a nice printout of the folder contents. Can process terabytes of disk space and millions of files.
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xplorer2 

All the shell goodies from windows explorer, none of the hassle! Plus all the features you would expect from a powerful tabbed dual-pane file manager, including Omni-Finder, a find files module that searches everywhere with arbitrary criteria
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ZipScan 

ZipScan searches archive files. It can search Zip, CAB, RAR, ACE, InstallShield CAB, JAR, TAR, GZIP and OpenOffice files, including password-protected, nested and self-extracting archives. Supports text searching. Can open and extract files.
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Useful File Utilities 

File browser with utilities (Replacer, Renamer, Finder, Batch Replacer, Case converter, Change attributes, Oem-Ansi converter). Possibility to add new utilities.
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