The fourth part of the Writing Secure PHP series, covering cross-site scripting, cross-site request forgery and character encoding security issues.

The Subversion Cheat Sheet, a quick reference guide for command line Subversion.

A beginner's guide to URL rewriting, with plenty of examples.

The second version of the Regular Expressions Cheat Sheet, a quick reference guide for regular expressions, including symbols, ranges, grouping, assertions and some sample patterns to get you started.

The second version of the mod_rewrite Cheat Sheet, a quick reference guide for mod_rewrite, with rewrite flags, regular expression syntax and sample rules.