Douglas Adams - Apple Visionary
Most people in the tech world know that Douglas Adams was a great fan of all things Apple. He allegedly bought the first Mac in the UK, he was the first to typeset a novel on a Mac, he published a home video using Quicktime on the internet a long time before YouTube was even a twinkle. He even gave Apple one of their advertising tag-lines:
"We may not have got everything right, but at least we knew the century was going to end."
Going back further it could be argued that his Hitch-hiker's Guide to the Galaxy foresaw the iPhone/iPad as a mobile source of information for travellers in the universe (or at least, the Earth)
I was re-reading the posthumous compilation "The Salmon of Doubt" last night and came to this article which I have read many times before but reading it again after the WWDC keynote it struck me just how much this sounded like what Extensions and Hand Off are trying to do.
There are many other articles on computers in the book, some of which are produced here
If you want to see more of Douglas's foresight, look for the documentary Hyperland or the BBC radio series The Hitch-hiker's Guide to the Future