Insults... whats your best?

[Robbie8666]

After overhearing 1 colleague refer to another as a "Cockwomble" (an insult I'd not heard in years!) got me thinking.. what's the best insult you ever heard, even if it was directed at you and you thought 'you know what, that's a good one I'll let you have that!'

I like using the term Wazzock! as people know its an insult but its not strong enough for them to retaliate to!