Not necessarily easter eggs I guess:
-Tomb of the Champion of Cyrodiil or something like it
-Imperial Legion Armor
-Gate to Oblivion (only 1 though, functioning or not)
-The possibility of a guard saying, "Stop right there criminal scum!" I wouldn't want that to be the only phrase they say though.
-Divine Crusader Armor maybe
The champion of Cyrodiil became lord sheogorath so we wouldn't be able to go to his tomb.