Apple's always publishing patents, but here's one that sounds rather fun: imagine an iPhone or iPad with a flexible display that has speakers built in to it, to provide surround sound.
The patent describes a flexible display with all manner of built-in features:
A tactile keyboard, laser mics and speakers. Much of this is made possible by the idea of a flexible display — which is some way off but by no means impossible to achieve. Once you can manage that, according to this patent, the world is your oyster.
For instance, shove an array of transducers behind the screen and you turn the whole thing into a giant speaker, which would go some way to sounding like a proper set of speakers. Vibration may be a problem, but that might be tolerable compared to the tinny sound you squeeze out of most mobile and tablet speakers.