GNU awk User's Guide - Regular Expressions
Documentation of the Regular Expression syntax used in GNU Awk.
Mastering Regular Expressions (Second Edition)
Book by Jeffrey Friedl. Includes table of contents, full index, an errata sheet.
Programming in Emacs Lisp - Regular Expression Searches
Documentation of the Regular Expression syntax used in Emacs Lisp.
Regular Expression Quick Reference
Tried and tested, single sheet quick reference card for regular expressions. [PDF file]
Regular Expressions - Single Unix Specification
Specification for regular expressions -- massive document, somewhat technical.
Regular Expressions HOWTO The Basics of REReplace REFind
By Pete Freitag. The basics of using regular expressions with ColdFusion's REFind, and REReplace functions.
Regular Expressions in ne (Nice Editor)
A description of the regular expression support in ne (Nice Editor).
Regular Expressions Tutorial
A tutorial and reference for many popular regular expression flavors used by programming languages like Perl, PHP, Java, C# and VB.NET as well as a description of general tools lik…
Regular Expressions: An Introduction
An essential guide to one of the most useful tools in the web development: regular expressions.
Seeing With C - Regular Expressions
A writeup on regular expressions connecting the math. and the CS views to regular expressions.