Pipes is maybe the only yahoo product I actually use. It's only for one frivolous thing though. Failblog (part of Cheezeburger I think? Doesn't really matter) Used to have a sub-blog called Hacked IRL. They shut it down a while back, but they still occasionally post clearly labelled Hacked IRL stories to the main Failblog. Since I liked Hacked IRL but really didn't want to have the whole fail blog feed subscribed, and I remembered having heard of Yahoo Pipes years before that, I looked it up and it was sure enough still around.

The result was this: http://pipes.yahoo.com/pipes/pipe.info?_id=5ead4957874f5a670...

Which is simply the fail blog feed filtered down to only posts containing "Hacked IRL" in the subject. I have the RSS of that subscribed.

Like I said, frivolous. But it only took a few minutes to put together even having never used pipes before.