1. An apparatus, comprising: (a) a computer system having a processor; (b) a speech engine configured to support at least an interface selected from the group consisting of one or more of a speech-to-text function and a speech recognition function, having a speech engine output; (c) a user interface, configured to present to a user an interactive advertisement selected from a plurality of different respective interactive advertisements, each interactive advertisement being associated with a respective data file defining a vocabulary and a grammar for interpretation of available commands associated with the interactive advertisement; and (d) a processor, configured to selectively process a speech command received in association with a presented interactive advertisement, based on the speech engine output and the respective data file.