In parts of Europe (most notably the U.K) a related but slightly different gesture is quite common; the index and middle fingers of the hand are extended (and slightly bent) and the rest of the fingers are curled inward. This gesture is often known as the V-sign, and is usually pushed upwards. It should not be confused with Winston Churchill's famous "V for Victory", which uses the same arrangement of fingers but with the palm facing away from the signer.
Legend has it that the "V-sign," originated with English and Welsh archers in the Battle of Agincourt, who used it to demonstrate to their French opponents that they still had the fingers needed to pull back their bows (prisoners' fingers were allegedly amputated to prevent them from using their martial skills).
As such it is a started life as a gesture of defiance, but has since become connected with phrases such as "Up yours" etc and is considered to be offensive.