Yahoo released a very interesting web2.0 application these days: pipes.
“Pipes is an interactive feed aggregator and manipulator. Using Pipes, you can create feeds that are more powerful, useful and relevant.”
It has a node based programming interface, which enables comfortable merging and editing of RSS Feeds. Some examples:

_ New York Times thru Flickr: Scans the NY Times Homepage for keywords and returns fitting flickr images. (reminds me a bit of my project “world’ notes“)
_ eBay price watch: search for a product on eBay within a certain price range.

I’m expecting it to become a very mighty tool, which enables is using RSS technology more focused and powerful.

Read more infos at O’Reilly’s Radar.