Sniff Keystrokes With Lasers/Voltmeters http://www.defcon.org/images/defcon-17/dc-17-presentations/defcon-17-barisani-bianco-sniff_keystrokes.pdf http://users.wpi.edu/~martin/MQP/hnathpettengill.pdf Differential Power Analysis Side-Channel Attacks in Cryptography not sure if smart grid would be able to get precise enough measurements to carry out attacks like these though here is something else about it http://spectrum.ieee.org/energy/the-smarter-grid/privacy-on-the-smart-grid?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+IeeeSpectrumTheGrid+%28IEEE+Spectrum%3A+The+Grid%29