I’ve always been a fan of the flavor items in MMOs since you can’t be killing all the time.  EQ really started this trend with horrendous downtime but WoW really pushed it farther with it inside jokes.

Dancing in particular I always found funny.  You can find some rather interesting dances if you look hard enough but the kicked for me is the animation.  Look at the what the original male Dwarf dance was, the progress to Draenei in Burning Crusade 2 years later, Worgen 4 years later and today, Pandaren.  Quite a huge improvement over the years, especially the last one.