"There are now three certainties in life — there's death, there's taxes and there's a foreign intelligence service on your system." ~ MI5's Head of Cyber
BBC Radio 4 recently aired a very interesting series on cyber espionage, theft, and war.
Reporter Gordon Corera interviewed numerous individuals including Michael Hayden (Former Director of the N.S.A.), Toomas Hendrik Ilves (President of Estonia), and MI5's Head of Cyber (who preferred not to be named). Episode 3 is still available for a limited time.