A "universal ad queue" (UAQ) is used for coordinating the display of at least two different types of advertisements to subscribers. The UAQ provides an ordered list for the display of ads to the subscribers. The ordered list may vary based on time, channel, program, previous ads, and subscriber type....http://www.google.co.uk/patents/US20020184047?utm_source=gb-gplus-sharePatent US20020184047 - Universal ad queue
