Of the classics, only "cunt" gets much reaction anymore. They're all so overused.
Even that not so much in the UK. But 'cunt' still has something of a single malt of curse words feel to it - shouldn't be used every day, but sometimes it's the only one that works.
The problem with 'cunt' is that you need the right accent to pull it off. It should sound very harsh, but 90 per cent of people will make it sound rather pathetic.
I can say it properly, so I enjoy using it, and it's probably the best swear word to tag another word on to. I like to use fuckcunt or cuntfuck. And I like scumcunt as well. One of my mates is a fan of bincunt, though I'm not sure why... maybe he wants it to mean 'massive cunt' as in 'you're a cunt that's as big as a rubbish bin'.