Yahoo! Pipes creates new pages by aggregating RSS feeds from different sources. Simple commands (sorting, counting, truncating) can be combined together to create output that meets your requirements.
This is how Pipes work
-Drag and drop editor lets you view and construct your pipeline
-You can fetch any data source via its RSS, Atom or other XML feed
-Extract the data you want, combine it with data from another source
-Apply various built-in filters as well as user-defined filters and much more...
Here’s how you can create your own pipe with Yahoo
Learn How to Build a Pipe in Just a Few Minutes on Yahoo! - YouTube
Yahoo pipes can be useful to
SEO in many ways
-Track the latest news in your industry (filtering by sources, keywords, or both)
-Track domain and marketplace offers
-Track inbound links
-Tracking all the major social sites and blog search engines
-See how other Yahoo pipes are spreading
-Watch price trends of any websites you subscribe to
-Used for monetization purposes (affiliate links in your Pipes)
Here’s Matt Cutts review about Yahoo Pipes
Review: Yahoo pipes