20. The method of claim 1 , wherein the action promotes interaction.
1. A method for associating an electronic document work with an action, the document work comprising text, the method comprising: a) electronically extracting within a client device features from the electronic document work; b) transmitting the extracted features from the client device to one or more servers; c) receiving at the client device from the one or more servers an identification of the electronic document work based on the extracted features, wherein the identification is based on a sub-linear search to identify at least a neighbor; d) electronically determining an action” based on the identification of the electronic document work; and e) electronically performing the action on the client device.