Favourite quests/missions in games.

[Count Igor]

Collecting 10 Boar Brains in WoW. And the best part? It's repeatable! You can spend half an hour getting Brains from Boars. EVERY DAY! Oh joy!

(It still puzzles me how some can survive without a brain)

 

[Babitz]

The Milkman Conspiracy in Psychonauts.

 

[tzimize]

Escorting Linken in ungoro on a pvp server T_T...wha..oh...favorite...

Suicide Mission / Jokers Quest in ME2. Also Talis/Legions Loyalty quest.
Dwarven Noble Opening in Dragon Age (if that can count as one quest)
The Paranoia Level in Psychonauts
Sniper Mission in CoD4 (the bombing run was a barrel of laughs too)
Pretty much any level in Max Payne/2
Pretty much any level in Hexen. Man that game had some of the most awesome and intricate/confusing puzzles/level design I've seen in ANY fps up untill now. And thats quite a few.

 

[HobbyJim]

"Save the princess...

By killing 16 giant monsters

Or just her evil mum

Cookie for both references"

Is it Shadow of the Colossus and Ico?

For me, I really liked the quest in KOTOR where you had to play as a lawyer in a case to try and get this dude out of jail on the planet Manaan (where all the weird fish guys were). Very interesting little sidetrack for the quest. Also, the scanning in the Metroid Prime series was a freaking sweet addition. It gave you so much more depth in an already deep game

 

[Thirsk]

The only level i specifically remember is the "Framed" mission from the old Thief II. You basically had to break into the City's police station and make it seem like the chief had stolen some thingy from the station's vault.

Great mission that.

 

[DustyDrB]

A great cliche: The Arena

(except in Fable 2, because combat is a snoozefest in that game)

but this guy picked my single most favorite

The Milkman Conspiracy in Psychonauts.

Good man.