This is what I have been waiting for.
It is a service that allows you to combine feeds and filter articles based on simple queries.
Combined with Google Reader it will allow me to filter out articles I am interested in from high volume feeds such as Engadget.
It is a pity that this kind of service is not integrated into Google Reader.
[I question wether this is going to be viable as a business though. How will they monetize it?]