Apple have applied for a patent whereby your headphones would act as a settings transfer system to bridge your new and old devices. Named "Data store and enhanced features for headset of portable media device", the application describes a set of headphones that would include an amount of flash memory; that would be used to backup speed-dials, equalizer settings, playlists, network connections and other preferences from your existing PMP or cellphone.
When plugged into the headphone jack of the new device - such as when you upgrade to a new iPod or iPhone - the headphones would transfer this information and thus instantly set it up with your preferred settings. Apple also describe a headset which could be controlled via gestures to a control section; for instance by sliding a finger down the microphone section of a hands-free headset, the volume of the PMP could be changed.
It seems unlikely that the flash memory involved would be too great - after all, if you were backing up your entire media collection onto your headphones, then you may as well use your headphones as an MP3 player - but for essential information or frustrating (or easily forgotten) settings like network passwords it could be a real time-saver. While the patent application does not specifically refer to it, it's also possible that the headphones could be used to temporarily swap settings, such as when listening to another person's PMP and wanting to use your own equalizer settings, or even to transfer basic data such as PIM or contact details.
[via Unwired View]