http://en.wikipedia.org/wiki/V-sign
The V sign is a hand gesture in which the index and middle fingers are raised and parted, while the other fingers are clenched. It has various meanings, depending on the cultural context and how it is presented. [...]
The sign's meaning depends in part on the way the hand is positioned. With the palm of the hand facing the signer, it can mean:
An insult – largely restricted to Australia, New Zealand, South Africa, Ireland, and the United Kingdom,[1] it means "fuck off".[2]
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The insulting version of the gesture (with the palm inwards) is often compared to the offensive gesture known as "the finger". The "two-fingered salute", also known as "The Longbowman Salute", "the two" and as "The Tongs" in the West of Scotland and "the forks" in Australia,[6] is commonly performed by flicking the V upwards from wrist or elbow. The V sign, when the palm is facing toward the person giving the sign, has long been an insulting gesture in England,[7] and later in the rest of the United Kingdom; however, this is quite untrue in America where it is used as a peace symbol; its use is largely restricted to the UK, Ireland, Australia, and New Zealand.[1] It is frequently used to signify defiance (especially to authority), contempt, or derision.[8]