via architizer.com
Giant animal mural, distrinctive style of Roa.
Spied on Chance Street, off Bethnal Green Road (near Shoreditch High Street station).
Updated 06/07/2012:
Here it is in daylight - less sinister.
Spied this earlier near Watney Street Market. Says it all really.
Street art : Old Truman Brewery, London.