In WoW, it was accumulating enough Goretusk livers from liverless boars and searching in vain for Mankrik's wife. In Star Trek Online, it used to be playing hide-and-seek with Sulu. In my main game, Lord of the Rings Online, it's doing the pie delivery run, or attempting to swim the frozen waters of Forochel, or falling to your doom in Moria.
What rite of passage do you remember (not so) fondly from your past and present MMOs? What experiences aggravated you when you went through them, and made you smile as you saw others go through the same thing and complain about it as you had? Where are those invisible lines separating the neophytes from the veterans?