Feed Rinse: "Feed Rinse is an easy to use tool that lets you automatically filter out syndicated content that you aren't interested in. It's like a spam filter for your RSS subscriptions"
Touchstone: "Subscribe to changes on your favourite website. Set rules for what’s important. Have alerts appear on your desktop while you work." They call subscription/notify/publish plugins as Input/Output Adapters.
Dapper: "Dapper’s mission is to allow you to use any web based content in any way you can imagine. And by use, we mean going beyond just reading or viewing a webpage."
xFruits: "XFruits makes possible the Mashup RSS creation in a very simple way thanks to the Composer. You can assemble the bricks together so as to build your own feed-based service.
"xFruiter" service's users are referenced. "