The Blue Peacock was a land mine developed by the Brits during the Cold War for use in West Germany in case of Soviet invasion. Its physics package had an output of 10 kilotons. It takes its name from the English "Rainbow" naming scheme, implemented because engineers were giving too many projects clever names that described the project in question too well. See also: Blue Danube. The Peacock weighed 7.2 tons, making it portable in a very liberal sense of the word. It had a problem with insufficient insulation during West German winters. A number of solutions were proposed, the most awesome of which involved using the body heat of live chickens to keep the electronics warm. The chickens would've had feed and water enough for about a week, which was the bomb's time limit anyway. When its file was declassified on April 1, 2004, the Ministry of Defense had trouble convincing the public that it was not an April Fool's joke.