My fave expressions:

"And then you woke up!"
"Not the brightest bulb on the tree..."
"Well that's a dirty little bastard!" in fact me and a friend say that so much we've shortened it to saying, "that's a DLB!" ;)

NOT with me it wont hahahah! :)
To answer your question from earlier, Kentucky girls are fed corn and soybeans

I say:

Fo' sheezy!
Geez Louise
Holy Crapemz
Good Deal
Good Times, Good Times
What the F*ck??!
Get outta here!
"And I'm like... (add what ever I said at that time)"
Holy Mother of God
Hell to da NAW

from Steele Magnolias
 

Looks like two pigs fightin' under a blanket (reference to fat people's butts)

"(enter something you dislike here, i often use drugs or smoking) is bad mmmmmmmkay?"

My usual... YGBSM:

You've
Gotta
Be
Sh*tting
Me!

And FUBAR:

F*cked
Up
Beyond
All
Recognition!

"Right."
"Oh Good God."
"Um, yeah."
"Not so much."
my friends and i always say "WTF?" (as in "double you tea eff?" hahaha)
"so....yeah."
"what HAAAAppened?"
another friend thing: "shuddup." "no, you shuddup!"

:)

"not the brightest crayon in the box"

Favorite Sayings
 

"Jimminy!"

"Hel-lo!"

When someone is especially un-nice and is in the middle of a diatribe, I look them straight in the eye and in the middle of their sentence say, "Of course you are." I then just walk off. Really leaves people confused!

"He/She just hasn't been the same since that house fell on his/her sister."

Silver

Oh My God. (not with pauses in between)
Oh hell yeah. (courtesy of an old WCW/WWF show I saw)
Bring it. (thanks to Jessica Alba, Dark Angel)
(on the last one I know, I know :p )

those are as queer as a three dollar bill

I say...

Hola, como esta? a lot
Riiiiiiight.
He's cut off.
What up playa?

"Stupid (only I say it stew-pid) Girl" - ala my friend Trisha

"It's my berfday" - ala Crank Yankers

"You're gonna get it!"

"I've got the magic stick" - a little work humor!

lmao
 

you guys crack me up! I have tons of these because these are how my friends and i communicate most of the time, and dude, i've got some wicked funny friends....here are some highlights---

"damn gina!"
"you're killing me smalls"
"Whatever major loser, fly away"(with a little gesture or two)
"He's so sad, he soaks his hands in beer hoping to get his date drunk"
"Who do i have to screw around here to get myself a box of easy mac?"
"Did I leave the oven on? No! I'm a squirrel!"
"Badgers badgers badgers badgers, mushroom mushroom!"
"Lick my balls, swallow my load and die"
"Aight, tight"
"Gravy!"
(two people talking)"would you kiss your mother with that mouth?""no, but i've kissed yours""that was you?!?! She said she had a boring night last night"

(I have a lot of gay friends I met through the theater department so when we meet a new ones, we rate them and describe them so we'll remember newer ones...I'm not gay bashing, please don't flame this, actually all of the comments we make, we've heard from the guys themselves)
*"He's so gay, he walks by rooms and they redecorate themeselves"
*"He's so gay, he scares himself at times"

Whenever someone flips me off or says "FU" I have an assortment to draw from....
*"Sorry, I give enough to charity already"
*"And what do you expect to do with the other 23 hours and 59 minutes of your day?"
(guys only)*"won't your boyfriend get jealous?"
(Good Female friends only)*"Sorry, I don't swing that way, and even if i did, I wouldn't date my friends"
*"Nah, I'm too tired to fake it"
*"Why would i want what the rest of the city has turned down?"