Oh, this is fun since I've lived a lot of different places...
Atlanta:
fixin to=am getting ready to do something, like "fixin to get dinner" (getting ready to cook)
y'all=you all
sack=bag
washroom=bathroom
coke=any kind of soft drink. "I want a coke." "What kind?" "Diet, large, no ice."
bless her heart=usually a prelude to an insult
Midwest:
pop=coke, sprite, etc.
warsh=wash (I personally never said this)
asshat=idiot
DB=douchebag (jerk)
Chicago-style dog=hot dog with mustard, relish, onions, pickle, and a tomato
half-assed=not really trying
cluster="traffic was a cluster" nicer way than saying cluster ****
shut the front door=you're in awe that something like that could happen
suck it=**** off you idiot
a moran=moron
jerkstore=from Seinfeld. George Costanza said that he "went to the jerkstore and they ran out of YOU!" Means you're just a real jerk
Ireland=
"will I..."=said as a question, "will I set the table" instead of "should I set the table?"
safe home=get home without problems
on the ****=drunk
I've the tea wet=warm up the water for tea
please God=an add on to many a sentence, "and he'll graduate, please God, blah blah"
Boston:
wicked=cool
it's killer=cool