A few of my favourites are:

You are a candidate for retrospective abortion.

You're an inspiration for birth control.

Anyone who fvcks you is too lazy to masturbate.

You use your personality for contraception.

 

F*&k U

 

Hey Stupid !!!!!!!!!!!

 

(to a girl) You're fat.

 

- I see the lighbulb over your head needs replacing
- You're a prime example of reverse Darwinism

 

twat

 

If ignorance is bliss you must be having an orgasm.

 

seldom right but never in doubt..........

 

Eat a D!ck!

 

Were you always this stupid, or did you have to take lessons?

You're so slow, you'd have to speed up to stop.

You're so full of shit, I could cut your head off and tip it out.

Yor head is so far up your ass, you're seeing double.

You sure must have been an ugly baby.