Here's a couple from Australia:
* She can talk under cement (think Lashawn)
* As ugly as a hat full of nuns' cu*ts (definitely not in polite usage)
* Bumping uglies (having sex)
* Do I look like someone who gives a f*ck? (used sarcastically, meaning "I'm not interested")
* Flat-out like a lizard drinking (very busy)
* Trouser snake (penis)
* Map of Tasmania (vagina)
* Point Percy at the porcelain (urinate - male)
* Technicolour yawn (vomit)
* Moon tan (pale complexion)
Kerry