1. At least one computer-readable memory, which is not a signal, comprising computer-executable instructions that, when executed by at least one processor, perform a method, the method comprising acts of: receiving inputs relating to a plurality of entities in a set, each input indicating approval of an entity in the set for another entity in the set; maintaining a database storing indications of approval associated with each of the plurality of entities in the set; processing the database to determine one or more clusters in the set, the clusters each comprising entities for which a metric of approval of members within the cluster exceeds a metric of approval from entities in the set that are not in the cluster, the processing the database to determine one or more clusters in the set includes: selecting an entity as a seed for the cluster; adding entities to the cluster, the adding comprising iteratively: for a candidate entity determining a fraction of indications of approval for the candidate entity received from entities within the cluster; and selectively adding the candidate entity based, at least in part, on the fraction being above a threshold; and after selectively adding the candidate item, selectively removing items from the cluster that do not meet at least one relatedness criteria; and presenting a suggestion, the suggestion relating to an action involving one or more entities and the suggestion being developed based on the one or more clusters such that the one or more entities are within at least one of the one or more clusters.