Abstract: Methods of digital content generation according to an aspect of the invention include the steps of receiving a request for a second digital content piece to supplement a first digital content piece being streamed to a user digital data device; determining a source of the first digital content piece and a locale of the user digital data device; inferring a type of the first digital content piece from the source of the first digital content piece and from a time for delivery of the first digital content piece to the user digital data device; selecting a digital content piece from among a plurality of digital content pieces, each of which is associated with one or more locales; and, transmitting, as the second digital content piece, the selected digital content piece or a reference thereto for delivery to the user digital data device in connection with the first digital content piece.