There was a bonus mission where you played Vader defending the Death Star in Rogue Leader (and you chose a ship from the Imperial hanger) bad video (sorry):
http://www.youtube.com/watch?v=aWuBwTYmTgA
and also there was the selection screen for playing the Atari games as an easter egg in Rebel Strike (as you approached the arcade machines the Meco Disco Star Wars played and the Imperial hanger became a disco with glitter ball and flashing lights, hilarious stuff).
http://www.youtube.com/watch?v=Itmi2R0ytfI&feature=related
Also from the same game more disco fun :