Talking about the HCI or Human Computer Interface, here is something interesting.
The multi-touch screen interaction experiments of Jefferson Y. Han have been a much talked about event lately. Jeff Han is a research scientist for New York University's Courant Institute of Mathematical Sciences.
In this video, Jeff Han demonstrates his intuitive, "interface-free," touch-driven computer screen, which can be manipulated intuitively with the fingertips, and responds to varying levels of pressure. This video was recorded in february 2006 in Monterey, California.
This may be the future of the way we use and interact with computers and machines. Apple's iphone is probably the first product in the market that uses the multi-touch technology.
YouTube Video Link