Apple has patented a power charger that also serves as a password recovery backup. If a user forgets his Macbook's password, for instance, he simply plugs in the cord, and it would provide a unique ID number stored in a memory chip in the adapter that acts as a decryption key, unscrambling an encrypted copy of the password stored on the machine. The technique, according to the patent, incentivizes better password use by avoiding traditional password recovery techniques that annoy users and lead to disabled or easily-guessed passwords. The new technique is only secure, the patent admits, in cases where the user leaves a mobile device's charger at home. So the idea may make the most sense for long-battery-life devices like iPods, iPads and iPhones rather than laptops, at least until laptop batteries last long enough that users don't take their power adapters with them and expose them to theft."