One writer? ok here goes, for me it was and in many ways still is: Alfred Bester, specifically " the demolished man".
whats yours?

The wonderful difficulty of choosing... um, I'll say its a story in this case: Tlen, Ukbar, Orbis Tertius (Borges).

In terms of my head being cranked open as a response to simply great writing then Salman Rushdie's Midnight's Children would be the one for me.

I've never heard of either Larry Niven or Alfred Bester so thanks for both the clip and sharing, wildcat

While this may not be the most original of choices, I'd have to say Stranger In A Strange Land by Robert Heinlien, of course.

I think I was about 11 or 12 when I first read it, in part because I felt I could somehow relate to the title, and I can say for certain that I haven't looked at life without some consideration of the book on what I see since then.

Wow. I don't know any of those authors and my choice is really not that deep. Haha. I don't even know the author. but the book was called "My Side of the Mountain". It was about a kid who's parents were gettings divorced who ran away to live in the forest on his own. WOW!
I was just little when I read it, but the mere idea that a kid could take his own fate into his own hands like that, rattled my world!! I have secretly wanted to live in a hollow tree ever since. *LOL* Hey, maybe that's why I turned out a tree hugger!

I love books that change my worldview.

Ender's Game by Orson Scott Card was the first book that I read over and over. There are still themes from that book that are prevalent in my life.

I honestly don't read that much fiction anymore, but recently, the works of Cory Doctorow (available for free at the link) have inspired me.

And, yes, I'll admit that I'm a huge Harry Potter fan and have been influenced by her writing.

Another would be "The Art of Selfishness" by David Seabury. A critical work for any seeker.

When i was about 16 and impatient of sending for 20,000 stamps 'on approval' i joined a bookclub for the three free books (whose titles i forget) then ran into major financial problems receiving unsolicited volumes. The first of these was 'The Magus' by John Fowles. I recently reread its author=edited last version, and as Fowles pointed out in his intro, it is technically a pretty crap book, a book for the eternal adolescent. But it changed my life for ever, by 17 i was reading the alexandria quartet (durrell), gnosticism, homer, anything about sexuality and black magic, etc etc. and all thing hieretic.