Figuring out where "30 Rock" ends and commercials begin requires a sharp eye thanks to American Express.
Recent episodes of the NBC series have been interspersed with the credit card company's so-called "podbusters": content segments featuring "Rock" cast members that appear right before the commercial break.
For instance, a viewer with an itchy trigger finger on TiVo's fast-forward button might have held off when "Rock" stars Jack McBrayer, Jane Krakowski and Scott Adsit appeared in a holiday-themed segment that had nothing to do with the episode's story line.
Watch an example from last night's episode:
From NBC, 12/13