I was reminded at the Code Camp that I hadn't posted a little application that I wrote to facilitate the creation and testing of regular expressions.  There are many tools out there that are downloadable that provide this functionality, but I found it easier to talk about regular expressions from an instructional standpoint with my own tool and demonstrations.

I therefore set out to create such an application and it's freely downloadable here.  Essentially, the program allows you to create regular expressions and test them against some text/file of your choosing.  You can also save off a collection of regular expressions to file so that you can create your own library of expressions.  If you attended the User Group meeting you'll find that I've enhanced the UI slightly to make it more useful and instructional.

NOTE: The download is the source code and requires the .NET Framework 2.0 to work properly.

Enjoy!