Something uttered by British people after they've been suckered punched. Usually preceded by the exclamation "Aw fuck", and accompanied by a look of complete bewilderment.
British guy: Blah Blah Blah Blah
British guy's friend: *punches British guy in the face*
British guy: "Aw FUCK, I can't believe you've done this!"
by Susake November 8, 2007
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the new meme, originating from the infamous youtube video

http://youtube.com/watch?v=8lBO23Dh23I
pete: hey, say thanks to your mum for me
sam: aw fuck, i can't believe you've done this
by crincled January 3, 2008
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A statement of frustration said when one is about to say something and is interrupted abruptly; usually with a punch to the face.

Note: It has to be said in a non-enthusiastic, brittish, calm and polite manner, if you will.

Example:

Some guy: "Hello everyone, i'm here today to talk about... *PUNCHED IN THE FACE*

Same guy: "Ah fuck, I can't believe you've done this."
by JoãoPaulo November 13, 2007
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