EN: Today's "wow": Yahoo! Pipes looks really like a cool web application. You can use it to combine, filter, sort and do much more with RSS feeds just by using the Pipe web-editor. The result is dumped as a new RSS feed.
O'Reilly radar has three articles about it, one by Tim O'Reilly in which he compares the new service to the pipe concept of UNIX and two (first, second) by Brady Forrest. All of them are a very good introduction to Yahoo! Pipes.