There is a great article on-line at acmqueue.com detailing the past, present, and potential future methods by which humans interact with computers. They cover advances made at Xerox's PARC and speculate about future technologies like perceptual interfaces. I don't know about all of you, but give me a good wireless laser-mouse and a clicky keyboard and I'm all set.
"Personal computing launched with the IBM PC. But popular computing - computing for the masses - launched with the modern WIMP (windows, icons, mouse, pointer) interface, which made computers usable by ordinary people. As popular computing has grown, the role of HCI (human-computer interaction) has increased. Most software today is interactive, and code related to the interface is more than half of all code. HCI also has a key role in application design. In a consumer market, a product's success depends on each user's experience with it. Unfortunately, great engineering on the back end will be undone by a poor interface, and a good UI can carry a product in spite of weaknesses inside."