One expression which will never become obsolete as long as we continue to elect people like this to the U.S. Senate: 
Taste or smell. Bad enough to knock a buzzard off a gut wagon. Hotter than 700 dollars. Wilder than a peach orchard boar. So poor I couldn’t buy half interest in a free sandwich. That land is so poor it wouldn’t raise hell sitting on a sack of fertilizer and a barrel of whiskey. He is so tight he wouldn’t give a dime to watch a piss ant eat a bale of hay. Tighter than the bark on a tree.
Tighter than a bulls ass in fly time.
Hotter than Dutch Love.
Sweatin like a whore in church.
Dumber than a box of rocks.
She’s so ugly, she’d make a freight train take a dirt road.
One expression which will never become obsolete as long as we continue to elect people like this to the U.S. Senate:
So poor I can’t even pay attention.
Happier than a dog with two d!*ks!
He’ll be a blowed up Jew! (My momma used to say that for about everything that might get someone hurt).
Filthy enough to gag a maggot!
Happier than a hog on ice.
Tighter than dick’s hat band! (I later found this was a reference to a condom).
It was a Mexican standoff! (Real meaning....I got whipped.)