I have been developing a totally free and open source script that:
* Grabs an article from an article directory.
* Rewrites it using a synonyms database.
* Gives you the option to rewrite, add or remove content.
* Add more synonyms to the database.
* Generate a second article to use it as a second reference.
* Automatically submits it to your website.
* In a future it will submit it to dozens of article directories.
The article generator is called MassiveArticles and the article submitter is called MassiveDirectories. The name of the whole set is MassiveSubmitter.
As I said, it's completely free of charge and open source. You can integrate it with your projects, redistribute it, etc. It's under the GPL license.
I'm constantly updating and upgrading the scripts. Currently, I uploaded some website templates that have the script already installed on them. In other words, you only have to download the template, upload it to your server and start pumping articles.
This is the website address: MassiveSubmitter - Open Source and Free Internet Marketing Software