PowerGREP 

Quickly search through large numbers of files on your PC or network using powerful text patterns to find exactly the information you want. Search and replace with plain text or regular expressions to maintain web sites, source code, reports, ...
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RegexBuddy 

Perfect companion for working with regular expressions. Easily create and clearly understand regex patterns. Test any regex on sample strings and files. Use the regex with automatic source code snippets. Collect regex libraries for future use.
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AJC Grep 

AJC Grep is a powerful file finder, text search, replace and data extraction program for Windows. This is a major time saving tool for developers, documenters, web designers and anyone who has to search and replace in a large number of files.
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