Man, I feel... networked!
Have you ever heard about Personal Area Networks or simply, PAN? Like the name says, it is a kind of network. The difference off this one is that the communication is established between computers that are close to a Person, usually devices carried by this person (cell phones, PDA's, MP3 players, etc).
The original ideia was to make data transmission using the body electric field. Nowadays the term has incorporated technologies such IrDA and Bluetooth, but still with the same essence: to share i/o, storage, information and computational resources among nearby devices.
If during a day you carry a cell phone, a MP3 player and a notebook, there will be more than one keyboard, speaker, screen and microphone available with you. Some redundancy here, hum?! Still the fact that, normally, all this stuff don't know what is happening with each other. With PAN you will be able to carry less power-hungry processors and mass storage, as the time devices can share their resources with each other, populating the nearby areas with data.
Take this as example: sometimes I listen to music in a mp3 player and if my cell phone starts ringing I can't hear it calls. If the devices were somehow connected, music could be paused and a sound could alert me about the incoming call. And more, if the mp3 player memory was full, the PDA one could be used instead to store music or too clothes could feel your health signals state and archive all information at your PDA, helping to diagnose any possible disease in the future.
PAN applications are limitless.
Another example, is the idea of an user coming home and his devices switch information with the house, updating schedules or simply informing other people in the house that he is present in the area.
All this looks too futuristic, right?! Wrong! It's true that still are lots of studies to be done in this field, but to prove that this ideas can already be used next time I will show a simple practical example of creating a way to recognize your presence at home. Exchanging information will be just few more steps... =)