1. A method of identifying and presenting a plurality of data items, the method including: receiving a selection that identifies a parent category; identifying a first category based on the parent category, the first category is a first leaf category; identifying the plurality of data items based on a link from the first category to a second category, the second category is a second leaf category that corresponds to the first leaf category, the data items are not user-classifiable under the first category and are user-classifiable under the second category, the identifying done at least in part through the use of one or more processors; and communicating, over a network, a user interface responsive to the receiving the selection, the user interface including the plurality of data items.