This viewer can display RSS feeds of version 0.91, 0.92, 1.0 and 2.0 as well as even the good old legacy format Scripting News 2. (Sorry, no Atom.)
Just enter the URL of any compatible RSS feed, modify the layout settings as you like and push the Reload button. When finished, copy the HTML code into your own web page – and voilà!
* A proxy server is needed for cross-origin requests.
Based on a work at https://p3k.org/source/svn/rss-box/trunk/.
Thank you, p3k organisation!