I have an XML Viewer web part that consumes an RSS feed and displays the results on a site page.
Now I would like to publish these results as an RSS feed from my site. How can I do this?
If you want to consume or aggregate RSS feed data and then expose it as an RSS feed itself, you need to write a custom page and do it with code - you will not be able to do this with out of box Web Parts. The CQWP provides the ability to expose itself as an RSS Feed, but it can only aggregate SharePoint List data.
Add in a content editor web part right below your XML web part. Add a cool RSS image from the internet, and make it hyperlink with the original RSS feed URL. It seems like bad karma trying to rip off someone else's RSS feed and trying to pass it off as your own.