RegexBuddy - RegexBuddy is your perfect companion for working with regular expressions.
DocFetcher - DocFetcher is a portable German/English open source desktop search application.
RegExr - RegExr.com is an online tool to learn, build, and test Regular Expressions.
Agent Ransack - Agent Ransack is a tool for finding files and information on your hard drive fast and efficiently.
RegexMagic - Use RegexMagic to generate complete regular expressions to your specifications by using RegexMagic's flexible patterns, instead of the cryptic regex syntax.
Everything by Voidtools - Everything. Locate files and folders by name instantly. Everything. Small installation file. Clean and simple user interface.