Banksy is an awesome street-artists from Bristol* (England) and probably the most loved/hated. Im in love with his artworks since i bought his book "wall and piece". Check out the great stencil art he does all over the world.
* Thanks to Abduzeedo-user "Simon" for recognizing the mistake.
CCTV (Closed Circuit Television) are the surveillance systems that often are seen in London. And now recognize that Banksy painted this pictures right next to one of these cameras.
Check out his portfolio http://banksy.co.uk/