Some great insults :)

* He is an intellectual virgin, he has never had an idea in his life.
* You are living proof that stupid people should not breed.
* Doe's your head hurt when you are that stupid?
* You remind me of opium, a slow working dope.
* Did you study to be that expertly stupid or does it come naturally?
* How can I keep an idiot in suspense? I'll tell you later.
* He had a pimple on his ass which turned out to be a brain tumor
* The sealthing technology used to hide your brain from all attacks of reason is impressive. Are NASA designing advanced retards now?
* When you speak, you do so in a way that makes slugs and other invertebrates look like Nobel prize winners.
* Just when I think, "Surely, this person has obtained and encapsulates the limits of human stupidity", you go and push the boundary even further.
* if you were twice as smart as you are now, you'd be chronically stupid.