Free extensions for Joomla!

Hello,
first of all, thank you for your amazing extension.
It is the most important extension of my site.

I would like to do a thing and i suppose, as it is now, it's not possible.
I would like to limit the text.
Ok, i know i can limit by a number of text chars, but it should be better to put stright in the page source, an html tag to stop processing the remaining text.
Let me explain:

I thought that if i put a tag like:
<GNEND>
in my article, your extension can match this and stop to show other text (if this tag is not present, the "text char" value should be used)

Is it possible?
Let me know.

Thank you anyway

P.s. I hope my english is good enough to be understood!