Skyrim Easter Egg - Mai'q the Liar

While due to his status as a series regular his appearance in Skyrim alone could be considered an easter egg, it's his purpose in the game (and the ones before) making him even more easter-eggish. Since his first appearance in Morrowind M'Aiq the Liar was used by the developers to address features the community wished for. For example he comments on the frequently expressed desire for a multiplayer mode by saying something along the line of "I don't see the point of travelling with friends. It makes splitting up the treasures much more complicated.". Note that while M'Aiq expresses the exact same behavior as the one in Oblivion (e.g. his obsession with calipers and his appetite for horses) it is implied by his dialogue and the time span of 200 years between Oblivion and Skyrim that he is the grandchild of the M'Aiq that appeared in Oblivion and Morrowind (which themselves covered a time span of six years).

Additionally he can found anywhere along the main roads as he wanders them randomly.