2008/12/09 at Stanford – see the event page for details
They call it the "mother of all demos".
On December 9, 1968, Dr. Douglas C. Engelbart and the Augmentation Research Center (ARC) at Stanford Research Institute staged a 90-minute public multimedia demonstration at the Fall Joint Computer Conference in San Francisco. It was the world debut of personal and interactive computing: for the first time, the public saw a computer mouse, which controlled a networked computer system to demonstrate hypertext linking, real-time text editing, multiple windows with flexible view control, cathode display tubes, and shared-screen teleconferencing.
It changed what is possible. The 1968 demo presaged many of the technologies we use today, from personal computing to social networking. The demo embodied Doug Engelbart's vision of solving humanity's most important problems by using computers to improve communication and collaboration.
On December 9, 2008 at Stanford University's Memorial Auditorium, SRI International will present a commemorative 40th anniversary of this historic event. Join us to hear original participants recount what led up to the 1968 demo, the drama of the demonstration itself, and its impact—which no one could have imagined at the time. Learn about Doug Engelbart's vision to use computing to augment society's collective intellect and ability to solve the complex issues of our time.
Bummer this 4.5-hour event apparently won’t be webcast :(
(via Greg Lloyd)