I just thought I'd mention this since until about a month ago, I had no idea about it myself! It is possible to perform regular expression matches directly in your mySQL query.

This is great news for me since there have been many times I've wanted to do just that. Today I finally found my first use for it: searching for items (matching a tag). Here's how this query looks, and how you can apply regular expressions to mySQL queries to.

SELECT * FROM `theia_content` WHERE `tags` REGEXP ',? ?theia ?,?'

Since I consider myself pretty knowledgeable with using regular expressions, this is going to make things a lot easier in the future for me. :)

Kudos to xandro for the info!