The American-speaker's guide to Proper English
Pukka lingo, Blighty style
We regularly receive missives from representatives of our American readership politely requesting clarification of the highly esoteric and colourful language for which El Reg is rightly famous - especially when our US brethren are confronted with terms such as "boffin", "blagger", "slag", "cobblers" or "prat".
Here's a recent email which demonstrates the problem:
Hi. I'm not sure if you are the right person I should be e-mailing, so if not, I would appreciate it if you either forward this to the appropriate party or reply with the correct email that I should send this to.
I am an American and I enjoy The Register. My only problem with your site is that I don't know a lot of your slang, i.e., bespoke, chav, bourses, etc. I usually look in the dictionary or Google the slang if I can't determine its definition by its context. I think a lot of Americans would enjoy your site more it you linked the distinctly British or European words to a dictionary so us "New World'ers" could more easily understand their meanings.
Even if you don't, much thanks to you and all of your fellow employees for the excellent source of tech-related news.
Avid Reader in the U.S. of A.
Well, we can't see what the problem is with "bespoke" (made-to-measure) - unless they don't have tailors on the other side of the Pond. Of course, "bourse" is a French word, so the less said about that the better. We take your point about "chav" , however, and have done a bit of trawling to see if we could find any online resources to help out our linguistically-impoverished colonial cousins.
First up, we have a rather useful compendium of Anglicisms from effingpot.com . Revelations include the fact that "throw a wobbler" means to lose one's rag, "off his trolley" indicates that the subject is completely rat-arsed and/or bonkers and that "pissed" actually equals "totally bladdered" and not (pay attention at the back there) "annoyed".
With us so far? Lovely jubbly.
Our second resource is a tasty interactive Flash animation  which offers spoken British translations of everyday phrases. So, "I believe what you just said is untrue" is correctly rendered as "What a load of old bollocks", while the currently useful "It is very cold" emerges as "It's cold enough to freeze the bollocks off a brass monkey".
Pukka. We here at Vulture Central are currently mooting the introduction of our own online glossary, but in the meantime can thoroughly recommend both of the above as basic primers. So, until we finally sort our arse from our elbow - which could take donkey's years - readers are advised to have a shufti, gen up and get it sussed and sorted in the lingo department. ®
The Ziff-Davis Guide To Britishers (and other foreigners) 
You don't know your ass from your elbow 
Forget Cockney and Popney, here comes Chipney 
Beware Greeks bearing Greeklish 
The color of irony