Courtesy of my friend Diane, comes this timely reference from the UK Guardian for visitors to the London 2012 Olympics. Read on:
London 2012: breaking the language barrier
A quick guide to London English (by an American)Katie Puckrik guardian.co.uk
A salutation posing as a rhetorical question. Do not answer: "I'm fine, thanks. How are you?", because your only response will be a mystified cock of the head, in the manner of a confused dog. You are not being asked to detail your present frame of mind and body. "All right?" is the British version of "Ça va?", and the acceptable answer is: "All right."
'Can I help you?'
The classic British expression of passive aggression, thinly disguised as a kindly offer. Delivered with a menacing snarl, "Can I help you?" is often used to discourage customers from browsing in newsagents, as well as in fancy boutiques perceived to be above the shopper's station.
Cockney rhyming slang
Foreigners have an expectation that people hailing from all corners of the British Isles converse in cockney rhyming slang. Great Britons, do not disappoint them. They have come a long way to spend their tourist dollars, so the least you can do is sprinkle your speech with "up the apples and pears", "have a butcher's", "it's all gone Pete Tong" or "nice Bristols!" Feel free to make up your own expressions and definitions, however. How can they question you? You're the "cockney", not them.
An informal and somewhat affectionate way to say "thank you". It is often confused by foreigners with "ta rah" and "ta ta", both of which mean "goodbye". The confusion is heightened by the fact that "ta tas" are to Americans what "Bristols" are to cockneys.
An adverbial modifier that shades the meaning of a statement. Americans use "quite" to amplify their enthusiasm for the adjective, in the way they would use "really", "very" or "totally". By contrast, if a Brit volunteers that a visitor is "quite attractive", they're only saying "fairly" or "sort of attractive". This ambiguous intensifier bestows a "damning with faint praise" effect on any word with which it is teamed.
In North America, "horny" describes the state of being in the grip of one's own sexual desire. In the UK, "horny" is used to describe someone else as sexually attractive. However odd it may feel for foreigners to hear themselves described as "horny" when they are not in the full throes of loin-fuelled yearnings, it is "quite" a compliment.
'Let's have an Indian!'
When meal time rolls around, a foreigner may have occasion to hear a Brit announce heartily, "I'm in the mood for an Indian!" or "Let's have an Indian!" Allow me to assure the visitor that, by and large, British people are not cannibals, seeking to feast on an actual person of Indian descent. Rather, they are merely indicating the cuisine of an exotic land in the form of a native of said exotic land.
See also: "I could go for a Chinese/Italian/Mexican!"...