PubSub notification service

I just ran across PubSub, which is an online service that notifies you of new information as it becomes available on a zillion different feeds that PubSub monitors. As their web site says:

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.

I haven't used the service myself, but it does seem interesting, especially as a way to both monitor lots of feeds and to filter the feeds for topics of interest.

-- Jack Krupansky