Would like to say thank you and recommend this plugin — makes creating a gallery or product catalogue using Joomla's built in 'blog' layout feasible. Great stuff!

This is exactly what I was searching for.
I wanted to use a custom image for each article as the read more link, and this mod let me do it.

I actually wanted the image to still show when you read the article, but this is easy. Just comment out the 3rd to last line of code:
//$article->text=preg_replace('#{readmorelink}(.*?){/readmorelink}#s', '', $article->text);

The image will still show but it will not be a link

Also, this mod DOES NOT work out-of-the-box with some 3rd party modules, eg YOOdrawer (www.YOOtheme.com)
However, it only took me 5 minutes to mimic the effect within that, I posted my solution in the YOOthemes forum.

The plugin automatically adds the link to the text, image or flash between the {readmorelink} and {/readmorelink}

Installation instructions:
1) Install the plugin
2) Activate the plugin
3) Add a {readmorelink} example before of the pagebreak line in the article editor
4) In Articles -> Preferences menu, you should search for "Show Read more link" and futher change it to "hidden" to prevent displaying the default Joomla "Read more" link at the bottom of the article introduction.

The "Alternative readmore link" is automatically hidden when you display the full article.