1. A system for storing and controlling access to data representing personal behavior, the system comprising: an ID retrieval apparatus configured to receive identifying information revealing an identity of an individual, to submit a request corresponding to received identifying information to an ID generation apparatus, to receive an anonymized user ID in return, and to output the anonymized user ID to the individual; a data engine comprising a data store and an access controller, the data store being inaccessible to the ID retrieval apparatus and being configured to receive and store personalized behavioral data, access to stored personalized behavioral data being controlled by the access controller, the personalized behavioral data being behavioral data representing behavior of the individual, which behavioral data are anonymously personalized with the anonymized user ID; the access controller being configured to control access to the personalized behavioral data by requiring that data access requests from service providers specify the anonymized user ID with which the personalized behavioral data are personalized to access the personalized behavioral data.