Facts :

• Selected Vocabulary Differences Between British and American English (uta.fi)

• American Culture and Language - England / USA vocabulary : differences (ilv.ucl.ac.be)

• Differences (peak.org)
  Why are there differences?
  Culture / Vocabulary / Idiom – oblique sayings / Grammar / Usage / Spelling / Punctuation & Symbols
  Geography / Time (extinct — obsolete — archaic — current)
  Jargon / Swear Words / Rhyming Slang, Cockney Rhyming Slang, and Backslang
  Translations / A Spot of Linguistics
  Canadian (World English)
  Obligatory Humour

• American and British English differences (Wikipedia)
  1 Historical background
  2 Pronunciation
  3 Grammar
  4 Word derivation and compounds
  5 Lexis
  6 Writing
  7 Keyboards...

• Declaration of Revocation by John Cleese (transversaltruth.blogspot.com)
  "Her Sovereign Majesty Queen Elizabeth II will resume monarchical duties over all states, commonwealths and other territories.
  Except Utah, which she does not fancy...
  
  
  
  
• US 2 UK - A guide on the differences between American and English culture (us2uk.tripod.com)
  
  
  
  

Listening :

• Choose a city and learn to talk like the locals. (slanguage.com)
  
  

• fonetiks.org - The online language laboratory (avec différents accents) - (fonetiks.org)

Vocabulary :

• A BRIEF ENGLISH-AMERICAN DICTIONARY (traditions-uk)

• What are the differences between British English and American English? (Woodlands Junior School)

• The English-to-American Dictionary (english2american)

• The Best of British - The American's guide to speaking British (effingpot) :
  "The seven sections (Slang - People - Motoring - Clothing - Around the house - Food & drink - Odds & sods)
  contain over 1000 words and expressions that differ in their usage between the US and the UK."
  
  
  
  
• British/North American Vocabulary - Main differences (englishclub.com)

• Common Words in American and British English (www2.gsu.edu)

• British, Canadian and American Vocabulary (www3.telus.net)

• British and American Car Words (frank_esl2000)

• Information: US to UK Cooking Conversions, Food Names - (hostelscentral.com)
  ex : "In the UK, when they say: Aubergine, In the US, it means: Eggplant"
  
  

• Cooking Measures and Conversion Calculator with British and U.S. Cooking Terms
  (Global Gourmet)
  
  

• Measures and Weights (englisch hilfen.de) :
  Linear measures -
  Nautical measures -
  Liquid measures of capacity (BRITISH and AMERICAN) -
  Avoirdupois weights -
  Temperature conversion

Grammar :

• American vs. British Grammar (englishplus.com)

INTERACTIVE exercises :

• British and American English - interactive exercise (British Council)

• British English or American English?
  "Is it Father Christmas or Santa Claus?
  The answer depends on which side of the Atlantic you are."
  - Activities created by Renée Maufroid :
  Matching - Flashcards (Java / non-Java) - Concentration - Word Search
  
  

• British - American English - interactive exercises (englisch hilfen.de)

• British/American Quiz (englishclub.com)
  "Match a British English word on the left with an American English word on the right."

• Idem (englishclub.com)

INTERACTIVE games :

• In the bathroom - interactive crossword (BBC)
  
  

Games TO PRINT :

• British and American English - a crossword
  "Complete the crossword with the American English equivalent of the British English words."
  - with Teacher's Notes
  (Inside Out)

Songs :

• Let's call the whole thing off - sung by Fred Astaire - Listen to it! (themillstone.blogspot.com)
  Differences British English / American English
  - with the lyrics :
  "You say eether and I say eyether,
  You say neether and I say nyther..."
  (lyricsdepot.com)

• Englishman In New York by Sting :
  "I don't drink coffee I take tea my dear
  I like my toast done on one side
  And you can hear it in my accent when I talk
  I'm an Englishman in New York"