Apple may shave a few millimeters from future iPods and iPhones by using a new patent for a new audio jack. The device uses Pogo pins as conductive contacts.
Current iPods use a standard cantilever design. A cantilever is a metallic beam that is folded inside the case, providing a contact with the metal stereo plug. When you put the plug inside the jack, the beams bend, but present enough resistance to make a good contact with the plug's surface. However, to have enough resistance, they need to have an adequate size, which is too big for Apple at this point.
The new patent employs Pogo pins, which have been used for a long time in electronics to provide with temporary connections between circuit boards. The Cray-2 supercomputer, for example, used these pings to sandwich boards together. The Pogo pings are tiny devices which contain a pin inside a metal cylinder. The pins will retract whenever you get the plug inside the jack, but keeps the contact thanks to a spring inside the cylinder. [Apple Insider]