 During the climactic shootout at Information Retrieval, the janitor  is killed and her vacuum cleaner rolls down the steps as the storm  troopers walk and fire their weapons in a skirmish line formation.  This is a reference to Sergei M. Eisenstein (qv)s film,  _Bronenosets Potyomkin (1925)_ (qv), when the Cossacks march down  the steps of the Port of Odessa, firing away as a baby carriage  rolls by.