h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

tea towel holder - the anus (funnier if you work it out for yourself)
badly packed kebab - a vulgar (but still excellent) term for the 'vagina'.
beef curtains - another vulgar term for a woman's 'bits'.

Anyone mention Brass Monkeys yet? Not very applicable on a day like today, but still...

No-one's added the word "nonse"... kind of a general yuppie insult.
I know not its derivation.

Hopefully one of the h2g2 PTB will go and get the Viz profanisaurus. It'll save people a lot of time.
I thought "nonce" meant something similar to "ponce", and that "ponce" technically means a pimp to young rent-boys.
Are phrases being included in this thing? "Gone all to b*****y" can't be left out.
What do you mean about the Eskimo and Snow thing in relation to York? How else could one describe a hundred-foot painting of an emaciated blue whale on a bit of netting in the park?
Why do "people" in London always say "cushtie" or however the hell they spell it? Do all Londoners do it or just that part of it imitated by David Jason? Someone needs to assign an ASCII character to the glottal stop to help foreigners recognise when they're being addressed by a Londoner.

"Cushtie" is not a word much used in London any more. However, "safe", "large", "blatently", and "Boyaka-shan" are depending on social circle.

better had else you'll go mad as a box of badgers.

Aha!

Rocking Horse S**t: a rare thing, seldom found

Similarly 'Hen's teeth' or 'warts on a cue ball'!

i'm off down the "frog and toad"(road) for a cup of "Rosey Lee"(tea)with me"China plates"(mates)as fast as my "bacon and eggs"(legs) will carry me.Then round the "jolly horner"(corner)to the "old rubber dub"(pub) for a large "VAT" (Vodka & Tonic). After all that liquid i'll need a long "gypsies kiss"(p***).
My next activity will be to fill my "north and south"(mouth)and run the "J edger"(Vacuum) over the carpet.If you have managed to read this far you will realise that this is all a load of "pony and Trap"

Laking - Playing out. Used by yorkshire children. As in "A' yuh comin' aht lakin(g) t'neet?"
RAF - Rough as f**k. Meaning that the person you are observing is particularly ugly/common.
Prat - Idiot.
Thick as two short planks - Stupid.
Nerks - Chips (English chips, fries in American).
Dooins - A thing. Often used when the true word cannot be remembered. "Have you see my dooins?".
Beck - Small stream, often man made and often near farmers fields.
S'ithi - See you. Used, for no apparent reason, to end sentences with. "I'm off to play darts, s'ithi.".
Bloater - Fat person.

I'll post more as I remember them.

West Yorkshire, perchance?

Shakespeare used it. Nonce

In Birmingham the word "bostin'" means good or more than good.
"Our kid" or "A'r kid" would be the equivalent of my good man.
"nadgers" are gonads

Do we have an expert on Geordie slang?

I know a few:
clarts - mud
spuggie - sparrow
y'bugger - a general response to most statements
gerraway - see y'bugger
Why aye - definitely yes.

The last three will get you through most conversations with a Geordie if used appropriately.

Aye.

Skitters - tyneside diarrhoea
buzz - kiss
wu - we
wor - our/your
blob - condom

I was in my local pub the other day and a guy said
"A Dukes please"
When I asked what it was he said
"A pint of fosters"
When I still didn't get he said "you know a Duke of Gloucesters!!!"
I liked that one.
A bit like modern age rhyming slang.

Have a look here for a bit of discussion on modern vs trad rhyming slang.
http://www.h2g2.com/forumframe.cgi?thread=13832&forum=65#p50922

Knackered - literally (i believe) tired after sex,
having come from London to stay in New York for a few months, I find this subject particularly relevant. it seems that everyother word is unfamiliar to the insular yanks!
Blokes - men (they were fazed by this)
Packed in - broken down
I just can't believe that I speak a different lanuage?!!

Could they cope with "Bollocks", or is that a personal question?

I will ask them, hang on - oh what a laugh - "what" they asked - "bullocks??!!" Nope they hadn't a clue - only one guy who listens to the sex pistols!!

and it's close cousin: "couldn't organise a f*ck in a field of rabbits".