FrankenFeed™ is an open source application written using Ruby on Rails. We built this application to merge multiple RSS or ATOM feeds (xml) into a single master feed. The idea is to allow a power RSS or ATOM user to manage a single feed for a novice RSS or ATOM user. For example, your boss can read RSS feeds in his email client, but he has not idea how to add new feeds much less delete old ones. You can use FrankenFeed to add new feeds to his master feed or delete old feeds once they are no longer useful.
We have released the FrankenFeed code using the GNU General Public License. Feel free to download the code, customize and/or incorporate it into your own application or website. If you improve the code please remember to upload your changes to the SVN.