Agent Ransack - Text Search Tool
I have downloaded and installed it: Looks good but I haven't had the opportunity to 'use it in anger'
Agent Ransack is a very powerful and easy to use tool for finding files and information on your hard drive fast and efficiently. You can search for file names or text in files with support for Regular expressions. When searching the contents of files Agent Ransack displays and highlights the actual text segments found in a separate window so you can quickly browse the results without having to open each file! The program features several wizards that can help you if you are not familiar with the use of Regular Expressions. Agent Ransack integrates into the Windows Find menu, so it is readily available to be used instead of the common Windows search dialog. The program also includes a very detailed help file.
Link and download: Agent Ransack