Beadlecombs reference to the elusive soup sandwich got me thinking about some of the stuff we say and ppl just look at us, especially up north.

I like:
Tits on a boar hog.
Fine as frog hair split four ways
Dry as cracker juice
Slick as deer guts on a door knob
Burn the bearings.... Thanks Daniel
Nervous as a cat on a hot tin roof
Too big a cat to get tricked by a kitten
Not seen you in a month of Sundays
Sweatin like a whore in church

Those aren't all, but the ones that i may use at any given time.
What's yours?