Regular Expressions (Regex) Construction Advice

Since posting this thread on the web development forum several months ago I've gotten very involved with regular expressions. If anyone needs some help understanding or constructing a regex, lemme know in this thread and I'll be happy to try to help as time permits.

For those who have no idea what I'm talking about, a regular expression is a special text string for describing a search pattern...basically wildcards on steroids. For example, here's a regex that will find most any valid email address:

\b[a-z\d._%-]+@(?:[a-z\d-]+\.)+[a-z]{2,6}\b

That will match "[email protected]", but not "[email protected]" or other invalid email address.

I could use that e.g. to check if someone entered a real email address in a web page, or I could replace it with whatever I want, which may incorporate all or only parts of the match (e.g. I could turn it into an HTML link).

Or maybe I want to find valid email addresses that are from anywhere but able2know.com ...to do so I'd adjust the regex pattern like so:

\b[a-z\d._%-]+@(?!able2know\.com\b)(?:[a-z\d-]+\.)+[a-z]{2,6}\b

As a web application developer, I now rely on regexes constantly in my work, but they can be very useful for non-developers as well (e.g. Microsoft Word allows advanced search and replace with a sort of quasi-regex support, and a number of other text editors including EditPad, which offers a nearly full-featured free version, support regex).

Want to take a list of names in Word and convert them to "Lastname, Firstname" format, or find any number that doesn't start with 0, or extract all phone numbers from a document, etc., etc.? A regular expression can help...