You may think twice before listening to you iPod during a thunderstorm after reading this story. A number of cases in the US suggest that listening to an iPod (or presumably any other device that uses headphones) can increase the severity of injuries suffered if you are struck by lightning. Obviously there aren't too many cases of people being struck by lightning in general, so the evidence is a little patchy, but the latest issue of the New England Journal of Medicine claims that while lightning will normally flash over a victim's skin (admittedly that is harmful enough by itself), the iPod's headphones can act as a conductor and direct a bolt of electricity straight into a listener's ear, potentially rupturing eardrums. One case is of a 37 year old man who was struck by lightning when jogging passed a tree listening to music. "Although the use of a device such as an iPod may not increase the chances of being struck by lightning, in this case, the combination of sweat and metal earphones directed the current to, and through, the patient's head," the doctors wrote - as a result the man lost over 50% of his hearing. So although it is relatively rare, you may want to keep this in mind if you want to get the safest experience whilst being struck by lightning.