One of Kingdom of Loathing's strengths is it's fine ability to integrate wit, pop-culture, and literature into a way that attracts all types of people. Below are just some of the references I've started to gather from items, locations, and encounters within the Kingdom.

This thread, brought to my attention by Firestorm Zero, was instrumental in gathering many of these references.

Slogan: An Adventurer is You!
Reference: "Engrish" taken from Nintendo Pro Wrestling.
Source: Urban Dictionary

KoL Context: Having 11 of something, you get the message: "It's ridiculous. It's not even funny."
Reference: The 1987 song, "Time Zones" by Negativeland.

Class: Disco Bandit
KoL Context: In the Department of Shadowy Arts and Crafts, when you need to slip under the bar to get to the bar, it says "You deftly maneuver (and muscle for rank)"
Reference:The song, "The Distance" by Cake.

They deftly maneuver and muscle for rank,
Fuel burning fast on an empty tank.

Class: Disco Bandit
KoL Context: Crossbow Fever skill: "You do not aim with your hand. He who aims with his hand has forgotten the face of Sneaky Pete. You aim with your Moxie."
Reference: Stephen King's amazing series, "The Gunslinger"

"I do not aim with my hand.
He who aims with his hand has forgotten the face of his father.
I aim with my Eye.

I do not shoot with my hand.
He who aims with his hand has forgotten the face of his father.
I shoot with my Mind.

I do not kill with my hand.
He who kills with his hand has forgotten the face of his father.
I kill with my Heart."
--The Gunslinger's Catechism, by Stephen King

Class: Sauceror's levels 3-6
KoL Context:

• level 3 - Parsley Enchanter
• level 4 - Sage Sage
• level 5 - Rosemary Diviner
• level 6 - Thyme Wizard

Are you goin' to Scarborough Fair? Parsley, sage, rosemary and thyme
Remember me to one who lives there, she once was a true love of mine

Clan items: Hobo-Flex (Clan Gym)
Reference: Bowflex workout equipment.

Clan items: Phantom Trollbooth (War Room of Clan Hall)
Reference: Norton Juster's 1972 children's novel, The Phantom Tollbooth
Source : misterx2000

Outfits: Bow Tux
Reference: Botox anti-aging system
Source: Chewbacca

Outfits: Trying to save a custom outfit without a name
KoL Context: Your outfit must have a first name. Whether it's O S C A R or not is your business.
Reference: Oscar Meyer's jingle:

My bologna has a first name
It's O S C A R
My bologna has a second name
It's M A Y E R
Oh, I love to eat it every day
and if you ask me why I'll say
Cause Oscar Mayer has a way
with B O L O G N A!

Action: Resting dream
KoL Context: You dream you're running through the basement of Cobb's Knobb. You enter the boiler room and get jumped by some freaky dude in a striped sweater and jaunty f3d0r4. He's wearing a glove with five razor-sharp pasta spoons strapped to it! He slashes at you and you wake up screaming... but it was
only a dream. Or ... was it?
Reference: Freddy Krueger of "Nightmare on Elm Street"
Source: dGnome

Action: Sell Stuff
KoL Context:You sell your (item) to a mechanic named Mike for X meat.
Reference: The band, Mike and the Mechanics
Source : Yendor