Smart electricity meter hacking can disclose which TV shows and movies you watch.

"At the 28th Chaos Computing Congress (28c3) hacker conference in Berlin, Germany researchers presented a talk titled "Smart Hacking for Privacy" where they looked into the privacy implications of "smart" electricity meters.

In Germany consumers who wish to contract with independent smart meter providers are able to have one installed in their home via a similar style of subscription you might agree to for a free cellular handset from a mobile phone company.
The researchers, Dario Carluccio and Stephan Brinkhaus, signed up with a company called Discovergy to see what type of information these meters collect, whether they were as secure as the company promised and what they might be able to determine from consumption patterns."

From Sophos Naked Security Blog link, Presentation 'Smart hacking for privacy' Youtube link
Great presentation on how electricity companies can exactly see when you are at home, when you make coffee or diner, at what times you sleep and even what shows and movies you watch by analyzing your electricity consumption footprint...