UserRssPortlet is a user-preferences-driven RSS-rendering JSR-168 portlet.
I've mentioned his half-finished RSS portlet a few-times on list. I'd like to finish it, probably re-working it to use Spring Portlet MVC to get a better understanding of Spring PortletMVC's support for JSR-168 render vs. action and caching, etc, but I never seem to get around to it. -Andrew
Doesn't completely work but is potentially a good starting point / interesting. Anyway, you're welcome to it, for whatever it's worth.