"PubSub is a matching service that instantly notifies you when new content is created that matches your subscription. Using a proprietary Matching Engine, PubSub is able to read millions of data sources on your behalf and notify you instantly whenever a match is made.  
The heart of the PubSub service is a powerful, proprietary Matching Engine that makes it possible, for the first time, to match millions of search queries against thousands of new pieces of information every second.  
Traditional search stores data and then allows you to find documents within that store of data. PubSub operates by first storing your subscription query, and then watching for new information that matches it. Your query will be checked against every piece of new information passing through our Matching Engine.  
Today, PubSub reads over 3 million weblogs, more than 50,000 internet newsgroups and all SEC (EDGAR) filings. In the coming months, we'll be adding many more streams of data, so stay tuned!"
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glitch p-udding: this thing is really freakin' cool. most innovative rss tool i've used.  
glitch p-udding: this is one of the most powerful tools freely available to internet users.  
beaglebot: I've been playing with it some and can't figure out if it's just a better way to do search feeds the way bloglines does or actually different  
fabulon7: I like bloglines the best so far, but I can't use it at work, so I use kinja there, because our content gestapo don't know what that is yet.
beaglebot: I've been playing with findory feeds to bloglines, working nicely so far