There's a lot possible here....a LOT!!!
In fact, in this article I wrote prior to the Lightning cable announcement, I propose that headphone jacks on portable devices might simply go away.
It is the most common failure point on those devices; hand-held manufacturers must hate those things.
Apple patented a flexible 3.5mm plug to reduce jack strain when inadvertently yanked out.
In 20 years (and likely a lot less) a headphone with a cable on it is going to look...