I've built a new Yahoo Pipes tool to overcome a quirk in the News Journal's RSS feed collection that has been bugging me. I call it The News Journal Aggregator.
The News Journal, Delaware's top daily paper, offers a number of RSS feeds. I've come to depend on them, in my Google Reader, to track stories from the paper. But the various feeds repeat each other sometimes. The same story might appear in both the "news" feed and the "politics" feed. And sometimes they repeat within feeds; I think this has something to do with republishing for small changes.
I don't know what causes it, but I got tired of the same stories multiplying within my Reader.
So I have built a Pipe to collect the News Journal's news, updates, politics, business and opinion feeds; filter them to drop any sports stories (I have other sources); filter them again to remove duplicates; sort them by date and time published; and publish them in a single RSS feed.