When you see a stereotypical terrorist or criminal, as depicted in movies, you almost always see them with AK-47s. Short for: "Автомат Калашникова образца 1947 года," this rifle has become the iconic weapon of rebels and guerrillas after World War 2. It is so widespread that the AK design was spread to over 55 national armies, and 100 million of the rifles have been produced so far.
The creator, Mikhail Kalashnikov, according to a BBC News article has expressed regrets over creating it:
"Mr Kalashnikov recently said he wished he had invented the lawn-mower instead.
He claims he has made no money from his rifle and is said to live on a meagre pension."
In 2006, Colombian musician and peace activist Cesar Lopez devised an AK converted into a guitar. One sold for US$17,000 in a fundraiser held to benefit the victims of anti-personnel, while another was exhibited at the United Nations.
I actually saw the one that you see above, which was set up in the UN building when I toured it last year.