Description
The chronological plugin works by placing the entries in chronologic order (oldest first) instead of reverse chronologic order (most recent first). It is only a demonstration plugin and should not otherwise be used except for demonstration or unless you want to output entries in a non-weblog way 
Installation and Setup
In your global /WEB-INF/plugin.properties file, add the following line:
chrono=org.blojsom.plugin.meta.ChronoPlugin
You may then add "chrono" to one of the flavor-based plugin chains. These plugin chains can be found in the individual user's plugin.properties file. For example:
html.blojsom-plugin-chain=...,chrono,...
Usage and URL Parameters
Usage
By including the chronological plugin in one of your flavor-based plugin chains, you should see your blog entries show up in chronologic order when displayed.
URL Parameters
There are no URL parameters to control the operation of the chronological plugin.
When you say demonstration, do you also imply "experimental"?
As an aside, I stumbled on this by Eric Meyer, design guru extraordinaire, who seems to think that blogs are broken already in their current form, http://www.meyerweb.com/eric/thoughts/2004/03/29/weblog-weirdness/
. The chrono plug-in may be a very important feature in the future...think about that for a moment...while everyone else scrambles for implementations of the "meyer-blog", blojsom already has support.