Rating: 

If you don't use regular expressions, this book will open your eyes to a much faster and cleaner way of doing a lot of what you probably struggle with every day.

Not only have I read it through, cover-to-cover, twice - I have permanent bookmarks in the book so I can find the parts I use all the time (the Perl section is particularly useful). Reading this book (and it's companion pocket reference) has saved me literally hours of time on some jobs, and made others possible. Some co-workers made fun of how much I read it - until they needed to understand a regular expression in someone else's code. Now they think it's wonderful.

Some of the best parts include details on the differences between Perl, grep, vi, Java, etc. Very well done. The examples are superb, and the occasional "quiz" lets you make sure you're really understanding what he's talking about. The author also includes references to other pages (instead of making you remember where you saw something