1. A non-transitory data processing system comprising: storage to store information files and associated metadata, the metadata indicating information about the associated information files, said metadata including typed-attributes usable in processing the information files; a database including a plurality of individually addressable user records, each including respective profile data structures, the profile data structures including therewithin a plurality of named interest nodes which are user-tunable channels, each named interest node data structure being logically connected with at least one target data structure, each target data structure being logically connected with at least one typed-attribute which can be logically connected by the user to any of said plural user-tunable channels at the user's option; logic executable to process the information files and associated meta data in response to a selected named interest node to produce a filtered set of information files using said at least one target in said selected named interest node, said meta data being produced by a person or an analyze engine performing analysis, extraction or classification on the associated information files; logic executable to compose and send executable documents via a network interface according to a communication protocol to a user terminal for rendition of a graphical user interface at a user terminal including display to the user of the interest node names, wherein the executable documents comprise data specifying a representation of the filtered set of information files and a representation of user selectable mark-up identifying typed-attributes represented by said metadata associated with the filtered set of information files; and logic to receive messages via a network interface according to a communication protocol indicating selection of particular mark-up in the graphical interface at the user terminal, and executable to modify the selected named interest node which is a user-tunable channel in response to said messages to add a target corresponding to the typed-attribute identified by the particular mark-up.