- Colder than a witch's tit.
- Colder than a ditch digger's ass.
- Cold enough to freeze the balls off a brass monkey.
"It's colder than a witch digger's brass monkey."
Even though it was about 25-30 years ago, I'm still using that one after hearing it on Mork and Mindy. For the infants among you, that was an ancient sitcom starring Robin Williams as the charming alien Mork. Classic stuff there. Click on the link if you want to see a really lame fan site.
OK, first blog of 2008. At least it's not a crocodile with a hand in its mouth.