Computer scientist Douglas Engelbart kicks off the personal computer revolution with a product demonstration that is so amazing it inspires a generation of technologists. It will become known as "the mother of all demos."
The presentation included the debut of the computer mouse, which Engelbart used to control an onscreen pointer in exactly the same way we do today. For a world used to thinking of computers as impersonal boxes that read punched cards, whir awhile, then spit out reams of teletype paper, this kind of real-time graphical control was amazing enough.
Englebert also demonstrated other computer abilities such as hyperlinks, windows, and videoconferencing, among other ideas we use today, although it took the computer industry decades to implement them. http://www.wired.com/science/discoveries/news/2008/12/dayintech_1209
In addition, Wired has a gallery showing the evolution of the computer mouse. http://www.wired.com/gadgets/miscellaneous/multimedia/2008/12/gallery_40_years_mouse
(image credit: SRI International)