I'd hate to say how many PowerPoint demonstrations I have sat through. And, yes, I've certainly delivered my share of them, too. In fact, in many places it is now difficult to give a speech without PowerPoint, and I am not sure that is a good thing. Now Peter Norvig offers a tongue-in-cheek look at "What if Abraham Lincoln used PowerPoint?"
Norvig offers Powerpoint slides for Lincoln's Gettysburg address, had Abe the modern "advantage" of computer technology. After looking at these slides, I'm glad that Lincoln didn't have this technology.
You can see for yourself at http://norvig.com/Gettysburg/