Open Source tool to find/replace text in multiple files.
Extremely simple to use. Command line support to run Replace using batch file.
Single file download - fnr.exe (127kb)
Replace text in multiple files using windows application or through command line
Find Only to see where matches are found
Searching for files in one directory or recursing sub-directories
Find and replace multi-line text
Generate command line button to create command line text to put in batch file
Command line help
Unit tests of Find/Replace engine
Download link is broken, but I've sent a replacement.
Fast and efficient, but note that all your file previous modification dates will automatically be changed, and you might not be able to get them back.