Just what it says on the tin.

Archived.

Enter a regular expression and some test data, and you can interactively debug and develop regular expressions in realtime for just about any programming language.

An online regular expression builder and explorer. Paste the text you're playing around with in the big window and start typing regular expressions in the expression window. It will visually and interactively highlight the bits of your sample text that your regexp matches in close to realtime (It's written in JavaScript so be patient with it). Great for debugging and whipping together custom digesters.

A silly page that has lots of useful stuff about unix, infosec, hacking, it, scripts, permissions, regexp, CLI tools, and other geek stuff.