A few years ago, I discovered Scripturizer - a javascript that finds Bible references in your web pages and turns them into links to the verses on BibleGateway. The script is fairly simple to add to your site, if you don't mind editing the HTML for each theme you use - until now.
ImpressCMS has added a preload functionality that allows you to automatically load scripts and I have adapted Scripturizer to work as a preload. Now, I can switch themes, or allow users to select their own favorite theme, and Scripturizer still does its job.
You can download this preload from our download area for core addons - you'll need ImpressCMS 1.1 for this to work, or you can use the scripturizer.js file in the /libraries/scripturizer/ folder and include the script in your HTML files for your theme.
So, now, references like Matthew 28:19-20 automatically link you to the text on BibleGateway. Look in the /preload folder and open scripturizer.php to see the options available.