I think I've mentioned this before on Ana's blog, but the questline where your kidney gets stolen and you have to get it back is one of my favorites in Rift. It takes place in a town with a substantial criminal presence, and it's very common to see a friendly NPC run up asking for help only to lead you into an ambush, but the criminals who ambush you are always easy to kill, so you get accustomed to the idea that obvious trap = free loot. And then you walk into the wrong obvious trap, someone knocks you out, and you wake up somewhere else minus one kidney.

Aion, sadly, had no quests I found terribly memorable, with the exception of the one where you had to punch pig-like animals to get them back into their pens.

To return to the topic of SWTOR, I was greatly amused by the Sith Inquisitor starter questline when the rival showed up. He was so over-the-top he might as well have had a giant neon sign over his head saying "You Will Need To Kill This Guy."