This dude, named Anand, runs his business of cheating just infront of the new Department of International Development building at Whitehall. He gave 10 pounds less for every 100 US dollars. Wouldn’t have given him the pleasure of ripping me off had I known his business practice beforehand. When I realized he was not giving me the normal rate it was late by about one minute. And he wouldn’t exchange the money back. Lesson: Don’t trust money changers even if you are in central London.