Patently Apple reports that Apple has been granted almost 20 patents covering various software and hardware implementations. The site has singled out three of these patents as the most intriguing of the bunch.
The first patent, Integrated Touch Screen, "relates to touch sensing circuitry integrated into the display pixel stackup (i.e., the stacked material layers forming the display pixels) of a display, such as an LCD display," according to Apple's description. The upshot of this patent is thinner and brighter displays that require less power to drive them; additionally, the displays will require fewer parts and manufacturing steps, potentially bringing down both their cost and the difficulty of manufacture.
It's unclear if the technology described in this patent has been implemented in Apple's products already or not. The iPhone 4's touchscreen is remarkably brighter, thinner, and more "integrated" than that on the iPhone 3GS, so it's possible Apple has already started using the technology described in this patent. Of interest, diagrams from the patent show a touchscreen implementation on a notebook computer, indicating that Apple has at least explored the possibility of a touchscreen Mac.
The second granted patent, Voicemail Manager for Portable Multifunction Device, essentially describes the iPhone's Visual Voicemail feature. As Patently Apple points out, this function which iPhone users take for granted today replaces the cumbersome hierarchical menu-style interfaces of preceding phones, which often made checking voicemail a frustrating experience. Apple filed for this patent over four years ago, almost at the same time as the original iPhone's launch.
The third patent, Component Retention Mechanism for a Tower Computer, sounds awfully similar to the modular hard drive bays in the Mac Pro. The patent expands upon this modularity by describing retention mechanisms for PCI cards. Most Macs aren't well-known for being easily customized, but the Mac Pro is definitely an exception to that rule.
The remaining recently-granted patents are far more esoteric than the three described above, but if you can wrap your head around them, Patently Apple has handy links to all of them.