Regex web testers and tutorials/books

Inspired by regexbuddy. Works pretty fine and is web so can be used if you are away of your usual workplace and preffered software

http://regexpal.com/

Here is another one -  http://www.rubular.com/

Here is a handy guide: http://www.regular-expressions.info/quickstart.html

Still work in progress but since i like the author here is a "Learn the hard way" book on regex: http://regex.learncodethehardway.org/book/