I interfaced at work with a guy 35 years ago who used the term "as useless as a tit on a boar hog!"

cold enough to freeze the balls off a brass monkey.

I think an interesting note: back in the days of Wooden Ships and cannons a brass triangle was mounted on the deck to stack cannonballs in, and it was called a brass monkey. in the extreme northern and southern latitudes when it would get cold that brass triangle wood contract and those cannonballs would roll all over the deck. Thus the phrase.

As cold as charity
It's cold enough to freeze the bollocks off of a brass monkey