iPhone Accessibility
One of the most remarkable demos i have seen is on Apple's site on how to use an iPhone without sight (yes, totally blind).
The video is on this page:
http://www.apple.com/iphone/iphone-3gs/accessibility.html#video
Amazingly, you can use all the built in functions, browse the web and compose and read emails etc without any sight. It looks incredibly easy too. The iPhone can even stay in your pocket.